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Planning stage - prior to seeds planted
- How can I decide whether to start from seeds, or purchase plants?
- Starting tomato plants from seeds is incredibly fulfilling, easy and fun. The selection of varieties available is simply huge - those who are Seed Savers Exchange members have 10,000 or more named tomatoes to choose from (all of which are heirloom or open pollinated), spanning every possible shape, size, color and flavor.
- However, it takes time and attention to succeed at starting your own transplants. Newly germinated seedlings are fragile and have particular needs. There is an ever-increasing selection of tomato varieties available as seedlings at farmers markets, big box stores, and seed companies. There is no right or wrong answer - it all depends upon you.
- What is the best way to decide which varieties to grow in my garden?
- Think about what kind of garden you want. Do you want to tell stories to friends and family and treat your garden like a living museum? Heirloom varieties would be a great choice. Heirlooms are also a good way to go if you want to save and share seeds. If you enjoy cooking and are creative, the vast variations in color, size, shape and flavor with open pollinated varieties will fit your needs perfectly. If you are limited to just a few plants, have significant disease issues, or have some specific production needs and want a more certain yield, hybrid varieties could be the best fit. There are some excellently flavored hybrid types for you to choose from.
How many tomato plants do I need?
This is not an easy question to answer….do you love, or just like, tomatoes? How many tomato lovers are in your family? Are you a summer-only tomato eater, or spend lots of time canning, freezing, and dehydrating your crop for off-season use? The answer is further complicated because of the wide variety of tomatoes available to grow...and variability season to season, variety to variety in any given garden.
A good rule of thumb for tomatoes that are happy where they are growing and with at least 6 hours of direct sun daily is 15 pounds of fruit per plant, spread across the span from first harvest to killing frost. This is only a rough average; you may get just a few pounds of fruit per plant if disease is an issue, critters are haunting your garden or the weather is uncooperative. On the other hand, you could get 25 to 30 pounds or more of tomatoes from each plant. Giving tomatoes away is never an issue, but not having enough can be quite depressing!
What do the terms indeterminate, determinate and dwarf mean?
Indeterminate tomatoes grow up and out and everywhere until killed by disease or frost; they can easily reach 10 to 20 feet in length and 5 feet in width. Most tomatoes are indeterminate in growth habit, and unless you are using large, wide cages, it is wise to prune away most of the suckers and support growth with a tall stake or another means of support, such as a fence. Sun Gold, Cherokee Purple and Lemon Boy are three examples of indeterminate tomatoes.
Determinate tomatoes are limited in height and width. They should not be pruned at all, are fine in a container and caged, and tend to ripen their large crop within a few weeks time. Though not as flavorful as a rule as indeterminate varieties, determinate types are great for sauce and paste making, due to the concentrated harvest period. Taxi, Sophie’s Choice and Roma are a few good examples.
Dwarf tomatoes combine the reduced height of determinate tomatoes with the prolonged fruiting and high flavor potential of indeterminate tomatoes. Unique in appearance, with a stout central stem and dark green crinkled foliage, they are fine for containers and caging. Dwarf Sweet Sue, New Big Dwarf and Tennessee Suited are a few examples of dwarf tomatoes.
What do the terms hybrid, heirloom and open pollinated mean?
A hybrid tomato is grown from seed that is held in tomatoes that result from taking pollen from the male parent and applying to the flower of the female parent. Because each seed originated from a hand-made cross, the cost is higher for hybrid seeds. Though tomato plants can be grown from seed saved from hybrid varieties, it will not breed true and look like the tomato from which the seed was saved; all sorts of things are possible, some resembling the male parent, some the female, and things in between. A hybrid variety can, therefore, never be an heirloom tomato because it does not reproduce from saved seed. Tolerance or resistance to various tomato diseases are often bred into hybrid varieties. Burpee’s Big Boy, Better Boy and Celebrity are three examples of hybrid tomatoes.
An open pollinated tomato is genetically stable, meaning that it will reproduce from saved seeds. All heirloom varieties are therefore open pollinated….but, not all open pollinated varieties are heirlooms. Examples of tomatoes that are open pollinated (but not yet heirlooms, in my view) are Cherokee Chocolate, Lucky Cross and Green Zebra.
Heirloom tomatoes are open pollinated varieties that have been in existence for many years, having been deemed of having such quality or sentimental value that someone along the line strove to ensure that it did not go extinct. The range of colors, shapes and sizes in heirloom tomatoes is staggering; there are thousands of named heirlooms. Some heirloom tomatoes are Cherokee Purple, Lillian’s Yellow Heirloom and Kellogg’s Breakfast.
What do the terms regular leaf and potato leaf mean?
The vast majority of tomato varieties have leaves that are “toothed” - not a smooth edge, but with indentations of various sizes and depths. Each tomato variety has a distinctive leaf shape and even color (various shades of green, from a more pale green with yellow tones, to a deep bluish green). Toothed tomato foliage is referred to as “regular leaf” foliage. Varieties such as Sun Gold, Dester and Aker’s West Virginia have regular leaf foliage.
If the leaf edges are smooth - resembling the leaves on a potato or pepper plant (both of which are in the same family as tomatoes), with no teeth or indentations, it is referred to as a “potato leaf” variety. The tomatoes Lillian’s Yellow Heirloom, Polish (Bill Ellis origin), and Green Giant have potato leaf foliage.
What is the difference between tolerance and resistance with respect to tomato diseases?
There are many different tomato diseases, some viral, some bacterial, some fungal and some even “critter” in nature. Tomato Spotted Wilt virus, Bacterial wilt, Early Blight (alternaria) and Nematodes (microscopic worms) are an example of each of these types.
When a tomato is said to be “resistant” to a disease, there is a mechanism for it to repel the agent responsible for entering the plant and causing harm. In other words, the tomato resists penetration by the disease agent.
“Tolerance” means that the disease agent enters the tomato using it’s preferred vector - roots, leaves, etc - but the tomato plant doesn’t suffer as a result.
In both cases - resistant or tolerant varieties - a region of high disease agent population will typically wear the tomato plant down over time. This is why hybrid tomatoes with various letters denoting bred-in resistances to diseases will eventually succumb if there is extreme pressure from the disease-causing agents.
If I grow heirlooms, am I doomed to lose plants to disease?
No one has ever done a well controlled study to test various heirloom tomato varieties in their resistance or tolerance to the many tomato diseases. Since so many older heirloom types are still available to grow, it follows that over time, some tolerance and/or resistance to various diseases has occurred. It becomes an exercise of trial and error to discover which particular tomato varieties will do well in your own garden. Making things more complicated are the fact that the variations of weather season to season mean that a given tomato with a great reputation should be tried more than once if it fails for you the first time it is grown.
Do I have to limit myself to certain varieties if I am gardening in containers or straw bales?
Any variety of tomato can be grown in a dirt garden, raised bed, container or straw bale, providing that there is sufficient sun and appropriate measures are taken to address the needs of the plant given its growing location.
Indeterminate tomatoes will do best in a container size of 10 gallons minimum. Dwarf or determinate tomatoes will do fine in a 5 gallon container.
No matter the growth habit, plan on planting two tomato plants per straw bale.
For containers and bales with tomatoes, support becomes the key. If your container or bale is on a solid surface adjacent to dirt or lawn, stakes can be driven in to the ground to provide support for the container or bale plants. Otherwise, creativity is the key. You can insert cages into containers or bales but the cages themselves need to be secured or they will eventually tip over. Make use of large containers or spent planting medium to provide support in areas like patios and driveways where driving stakes into the ground is not possible. By planting the stake in the un-planted container of dirt for use to stake a plant in an adjacent container - separating the stake from the container with the plant - you will achieve more stability over the season.
What are some good guidelines for choosing the source of my tomato seeds
A good starting spot is to look at The Garden Watchdog website to see if a company you are considering has a rating. Of course, this is the internet, so ratings on this site are just one component of a decision to order seeds from a particular company. Here's the thing - the quality of the seed, and accuracy of its identity, will play a huge role in all that comes after germination. For me, historical accuracy and varietal accuracy and seed purity are all paramount. Feel free to ask me for my opinion, ask gardening friends, consult the link above. With thousands and thousands of tomatoes, mix ups are easy, and it is possible that all seed sources neither grow the seed they are selling, or even know much about the variety - the field is that vast and complex. Let your first decision be a good one.
How can I match the hours of sunlight on my growing area to the tomatoes I choose?
Another way to avoid garden disappointment is to know about the hours of direct sun received in different areas of your yard and garden. A few hours of sun will give reasonable results with small fruited (cherry) tomatoes. At least 8 hours of direct sun is recommended to attain success with really large fruited varieties - the heirloom beefsteak types, the huge bicolors, Mortgage Lifter and the like. Degree days are also important in terms of mitigating the sunlight hours....warmer areas (more degree days) will lead to more success with large, long maturing varieties with less than optimal sunlight.
What is the difference between a red and pink tomato?
There are two ways to answer this. Keeping strictly to color, the appearance of a tomato is a combination of the flesh color and the skin color. Pink tomatoes (sometimes called crimson, or rose - or even purple in old seed catalogs) are red fleshed and clear skinned. Red tomatoes (also referred to as scarlet or red orange) have red flesh and yellow skin. As far as flavor, each tomato variety, no matter what the color, will have the flavor programmed by its genes, and color is not a factor. Since many of us "eat with our eyes" and have possible flavor expectations based on our eating history, we may think that a red tomato will have a different flavor than a pink - or a yellow, or a green - or any other color for which we may have preconceptions. The best way to answer this question is to grow differently colored varieties, examine the apparent color, then the internal color, then the skin, to teach yourself a bit about it.
Do different colored tomatoes taste different?
I go into this a a bit in the question above. Each tomato variety - each of the thousands of different types - taste either slightly or extremely different. The dependency is not on color, but on the various flavor components directed by the genetics of each particular variety. There are sweet, sour, bland, intense, balanced examples in each color.
- How can I decide whether to start from seeds, or purchase plants?
Do I need a greenhouse to start my tomato plants from seed?
Absolutely not! I've never had a greenhouse and start thousands of seedlings each year using but a sunny window in my office, a table, sheets of plug flats, inexpensive heat mats, and attention to detail and timing. Check out a series of videos on my resources page to find out how I do it. There is a lot of detail on this topic in my book Epic Tomatoes as well.
When should I plant my tomato seeds?
I've developed a general rule of thumb for timing if starting tomato, pepper or eggplant seedlings from seed. Decide on the date that you will set the plants into your garden and work back two months. That is your seed planting date. As an example, I aim for the possibility to plant out on April 15 (that is typically safe in terms of overnight temperatures of 32 degrees - the frost temperature - or less). Given that, I expect to be transplanting seedlings into separate, larger containers on March 15. My date to plant seeds is therefore February 15. This type of planning has worked well for me for many years.
What are the most important factors to consider in successful tomato seed starting?
Quality of seed, quality and nature of the seed starting medium, temperature, moisture, attention to detail (disciplined monitoring of progress) and planting depth are all critical factors in successful tomato seed starting. I will take these separately.
Seed quality - home-saved seed that is kept dry and at a reasonably even temperature will germinate well up to 12 years or more. I've found that germination drops off significantly at 14-15 years of age.
Seed starting medium - it is important to use a sterile seed starter so that troubles are avoided at the very start. Also called soil-less mixes, a good seed starter is quite fine, fluffy, yet absorbs water well and drains quickly. It is typically a mixture of shredded bark, peat moss, perlite or vermiculite, and sometimes trace amounts of starter food and a wetting agent. There are many brands available; be sure to search for a seed starting mix.
Temperature - tomatoes will germinate more quickly with some added bottom heat; the air temperature should be at 60 degrees or more. Light is not necessary for seeds to germinate, but once up and out of the planting mix, light is critical - either from a sunny window, artificial lighting or direct sunlight.
Moisture - Even moisture is important to trigger seed germination, and sufficient water is necessary so that the newly germinated plants don't wither and die.
Planting depth - I find that shallow planting (1/16 of an inch or so) will lead to germinating tomato seeds within 3 to 5 days.
My process for starting tomato seeds successfully: Fill a container with bottom holes with a good quality seed starting mix to just below the top. Water well until it seeps out of the bottom holes a little bit. Smooth the surface with your finger, and sow the seeds onto the surface. Sprinkle dry seed starter over the seeds until they are just covered (very shallow planting). Mist the surface using a water spray bottle, loosely cover with plastic wrap or use a plastic dome, and put the container in a warm place; a heat mat under the containers will speed things along. Each day flip the plastic wrap, or let some air into the dome. You should see germination beginning within 3-4 days. Once most of the seeds germinate, remove the plastic wrap or dome. Ensure that the containers are watered well; don't let the seedlings dry out and wither. If the flat is in front of a sunny window, turn it 180 degrees daily to minimize bending of the seedlings (phototropism).
- Just after germinating, the seedlings are falling over, and the stem near the soil surface is pinched...what is going on?
- Damping off disease happens when a fungus attacks the young seedlings, causing the pinching and leading to seedling death. Use of non-sterile planting mix or leaving the plastic sheet on too long (or not flipping it regularly) can lead to damping off.
Transplanting INTO A LARGER CONTAINER
What are the benefits of transplanting?
Tomato plants grow quite slowly from seed, and it is quite typical for home started seedlings to get quite leggy (stretched plants with very thin stems that reach for the light). In addition, those who use a dense seeded planting method need to separate the seedlings into individual containers, essentially guaranteeing the need to transplant.
Any part of the stem of the tomato that is under the surface of the planting medium will develop additional roots, leading to a nice stocky seedling that will have a smooth transition to the final space in the garden. Transplanting deeply remedies any legginess that develops in seedlings.
What are the most important factors to consider when I am ready to transplant my seedlings to larger containers?
As with seed starting, using a high quality planting mix is critical. Using garden soil or inexpensive products such as bagged topsoil can introduce unwanted pathogens to the plants via the roots or direct contact with foliage. I recommend a top quality soil less mix, the same material used for seed starting.
Plan to transplant from your seed starting to larger pots at about one month from seed planting (one additional month from the transplanting activity should result in plants that are ready for the garden).
I've found that transplanting into dry planting medium minimizes any potential damage to the fragile seedlings. I fill a flat of containers (such as a strip of 18 3.5 inch square pots that fit nicely into a web flat) with the planting medium. The seedlings can then be easily nudged into the planting mix right up to the first true leaves.
Water each plant well and set them out of direct sun - the seedlings have likely yet to be hardened off. Give them 3-4 days at that location, then ease them into the outdoors slowly - perhaps one hour of dappled sun the first day, double it the second, go for direct sun the third day.
Pay attention to the weather; windy cold rain will make your seedlings look quite unhappy. Night time temperatures must be above freezing. Yet, tomato seedlings will do fine left outdoors even when the temperature falls to the mid 30s. If you are unsure as to the possibility of frost, return them to a safe warm place, or cover the flats of plants with floating row cover; this provides a few degrees of protection.
What if my plants get too leggy from leaving them in front of a sunny window too long?
This is not a concern, since it can be remedied by transplanting deeply, up to the leaves, What is important, however, is to try to get some direct sun shining on the transplanted (formerly leggy) seedlings so that the legginess doesn't develop once more.
What are the most important things to take into consideration when planting my seedlings into the garden?
For tomatoes to thrive, they need good drainage, adequate sun, an air and water permeable mulch, decent spacing, an appropriate pH and a good balance of nutrients.
Drainage: if you dig a hole, fill it with water and it takes hours to drain, the tomato roots will have wet feet and be very unhappy. Either dig deeply, remove excess heavy clay and add compost or planting mix, blending in some of the clay if desired for water retention. Alternately, you can hill soil on either side of your row of tomato holes to create a mound a foot tall or so. Place the tomato seedlings into the mound, planting deeply; excess water will drain out of the side of the mound.
Sunlight: Tomatoes love sun, and the largest fruited tomatoes need at least 8 hours of sun to produce well. The less hours of direct sun, the smaller fruited tomatoes should be selected.
Spacing: Crowding tomato plants so that foliage of adjacent plants becomes entwined can lead to easy spread of fungal foliage diseases. It is best to space 2 to 3 feet apart, so that there is air circulation and sun exposure around all parts of the plants and in between. If you stake the plants and prune to just a few growing stems, they may be able to be set closer; some foliage removal will help as the plants grow to create some space in between.
pH and nutrients: Tomatoes will do fine at a pH between 6 and 7 (neutral). Soil more acidic than pH 6 will impact uptake of nutrients critical to fruit formation and could lead to blossom end rot.
Young seedlings need not be fed right away, as there should be sufficient nutrients in the soil or planting mix to get them off to a good start. Be sure to start feeding a balanced plant food within a few weeks.
Mulching: Tomato plants will get off to a healthier start if a mulch is applied just after planting so that soil isn't splashed onto lower leaves when it rains. Untreated grass clippings, shredded hardwood bark, shredded newspaper and shredded leaves all make good mulch. Plastic sheeting can be used, but holes should be cut into the sheet so that water can enter.
What types of containers can I use - and what sizes are best
Anything that holds planting mix can be used to grow your tomatoes. Drainage is important - tomatoes hate wet feet - so there need to be bottom holes, unless you are using specially designed self watering containers. I would also avoid clay pots (Terra Cotta) because they will lose moisture too quickly through the container walls.
Aesthetics are often a guide to what you use, since your container plantings may be in a spot where visual appeal is important. Otherwise, go with the least expensive option - plastic rigid pots (the big black ones that trees and shrubs come in are great), or plastic grow bags, are my choice. Containers can also be used for many years.
If you are aiming to grow tall growing - aka indeterminate - tomatoes, 10 gallon capacity is recommended at a minimum. For determinate and dwarf growing varieties, 5 gallon capacity containers work fine.
I like to use inexpensive black plastic grow bags from Peaceful Valley; they've served me well for many years.
How do I get straw bales ready for planting?
A few brief pointers....purchase the bales from a reliable source that can confirm that there are not residual herbicides (I lost plants to some killer bales a few years ago). Purchase the bales at least two weeks before you plan to plant them. The preparation involves heavy doses of nitrogen for a week (alternating days, with deep watering each day), followed by application of a large dose of a balanced food and more watering. Two weeks after you begin, the bales are ready to plant. You can top them with a few inches of a good quality planting mix and direct seed some types of crops, or create divots and insert pre-started seedlings with other crop types. Everything you need beyond this brief summary can be found in the links in the prior bullet point.
Should I let my tomato plants sprawl, or cage them, or stake them?
This is a matter of how much space you have, where you garden, and the presence or absence of tomato plant harming pathogens in your soil. Tomatoes also attract many types of critters, and sprawling plants are easy prey. Rabbits, squirrels, raccoons and slugs may find your low-grown tomato crop irresistible.
Indeterminate tomato varieties will occupy a very large footprint if allowed to sprawl. If this is your choice, it is advised to lay down a layer of mulch, such as wheat straw, landscape covering, or plastic, to minimize contact of the soil with the foliage.
Caging works well with tomatoes, but the types of cages need to work for the growth habit of the tomato variety. Short cone shaped cages that are 3 or 4 feet tall will be fine for determinate and dwarf growing tomatoes, but are not useful for indeterminate types. Cages made from concrete reinforcing wire or cattle fencing, creating cages 5-6 feet tall and 3 feet wide, will work best.
Staking is the answer for indeterminate varieties with spacing of 2 to 3 feet - bamboo, wood or plastic coated metal stakes of 8 feet tall or more will assure that the plants will have plenty of upward growth room with ability to support to the stakes with string, twine, strips of cloth and any other means you can come up with. A variation on staking is the Florida weave and variations, where strong supports are driven into the ground at intervals, with strong wires or string running between the supports. The plants are grown at intervals between the supports and woven through the wire or string as they grow.
I’ve heard that planting tomatoes deeply is a good idea - why is that?
Leggy tomato seedlings with only the root ball planted into the soil leaves lots of tender, fragile stem exposed. A windy day can snap the plant. Any part of the stem of a tomato plant will root, meaning stockier, more robust plants.
Do I have to rotate my garden every year so that I don’t plant tomatoes in the same place?
It is true that tomato diseases can accumulate in areas, leading to reduced performance. However, although many issues can plague tomatoes, the most common (Early Blight - aka Alternaria - and Septoria) act on the surface of the tomato leaves, and don't attack the plant through the roots. Therefore, if your tomato plants do well in your garden and you are not losing them early to issues such as Nematodes, Fusarium and Verticillium (all of which are "in" the soil), you can keep planting them in the same area. Be sure to mulch well to keep soil from splashing onto the foliage, space adequately and replace the nutrients that were used by the plants during the previous season.
Can I reuse the potting mix in my containers and grow bags?
I've had a change of heart over the past few years with regard to the answer to this often asked question. It is an important one to answer because the cost of the planting material for container gardeners is quite significant.
Previously I've recommended all planting mix be tossed and fresh mix used each year. The prior season's planting mix can be used on non-tomato family crops, such as peas, beans, and greens.
I did some thinking and realized that container grown plants often escape the dread root-vector tomato diseases such as Fusarium wilt. The worst that happens to the vast majority of my container grown tomato plants is the typical lower foliage attacks of early blight and septoria. Changing to fresh potting mix won't eliminate those issues.
So my new advice - if your plants did well, sure - reuse the mix - but do top it with enough fresh planting mix to bring the level back up to within a few inches below the edge of the containers. Be sure to feed the plants well, since the nutrition likely leached out of the planting mix from last season.
What is a good schedule to follow for ensuring good success with my tomatoes - tying the plants, watering, feeding, pruning (suckering and topping). and monitoring for critter or disease issues.
The maintenance schedule and activities vary a bit depending upon whether your tomato plants are in a garden, raised bed, container or straw bale.
In general, indeterminate tomato varieties can gain up to 2 inches per day, and dwarf and determinate varieties 1 inch per day. This rapid growth rate means that you will be tying the plants to the stake or other support as they grow at least weekly.
Daily tomato maintenance activities can be watering (if you are using container or straw bales) and monitoring for diseases and critters.
Weekly tomato maintenance activities can be feeding (if you are using containers or straw bales), tying to supports and suckering.
Regular observations are recommended, as things can change and happen fast in the garden. Keeping a gardening log is a great way to record what is happening, and when; this can be referred back to during future garden planning. As I say often, it is easier to prevent issues from occurring than remedying them once they hit.
What are suckers and how should I deal with them?
Suckers, or side shoots, are the growth that emerges at a 45 degree angle between the growing stem and the leaf stalk. Suckers emerge on suckers themselves. Because of this, a tomato plant can become dense and complex very quickly.
Suckers are neither good or bad; leaving them doesn't reduce tomato size or put stress on the plant, and removing them doesn't make for larger tomatoes. The strategy to sucker or not to sucker - or something in between - relates to how you plan to grow and support the plant.
Suckers are a concern mainly for indeterminate tomato varieties. Determinate tomato varieties should not have suckers removed (the yield will be drastically reduced), and dwarf tomato varieties don't need to have suckers pruned (since they stay so compact - and again, it will reduce the yield).
Indeterminate tomatoes that are grown in large cages need not be suckered. Since the growth will be rampant and yield potential high, be sure to compensate with watering and feeding.
For staked tomatoes, you can choose to let a particular number of suckers to advance, removing the rest, to fit the desired width of the plant; this is an important consideration for plant spacing. One method I've been using recently is to allow for 3 or 4 suckers to grow on at about 2 feet up the plant, removing the rest below. I then let suckers develop above until the top of the support is reached, at which time I top the growing tips. Sisal twine can be used to tie the plant and all of the growth to the central stake using large loops of twine.
What can I do if the tomatoes on my plants end up being exposed to the direct rays of the sun?
Removal of diseased foliage can lead to exposed tomatoes that are in direct line to the intense summer rays of the sun, leading to bleached, damaged areas. (Tomatoes do not need direct sunlight to ripen).
Ways to minimize sun scald are being judicious in your pruning of suckers and foliage so that the green fruit retain some shading. If disease warrants foliage removal, exposing the tomatoes, fashion a covering or screen around the fruit by using newspaper woven around the plant support.
What is the best way to water my plants?
Wet tomato foliage is a magnet for spores of such diseases as early blight and septoria, leading to spotted tomato foliage that works its way up the plant. It is advised to never water plants using a sprinkler or from above with a hose; this is very inefficient as much of the water will evaporate or adhere to the foliage and not make it to the root zone. Use a hose, soaker hose or drip irrigation to ensure that the water is applied at the base of the plant.
What is the best way to feed my plants - and what should I use?
My experience tells me that as long as you are using a high quality planting mix or have good, rich garden soil that you are replenishing with nutrients, the exact nature of the tomato fertilizer is less important than ensuring that you are feeding them adequately. How often to feed depends upon where/how you are growing them.
Traditional garden (dirt planted) tomatoes have the area below the plants to hold nutrients for the use of the tomato plant roots. The plants, therefore, don't need feeding as frequently as those grown in raised beds, containers or straw bales. Regular feeding - every few weeks - using the recommendations on the product of your choice should suffice. The bigger the plants, more vigorously growing, and more watering needed due to hot weather means increasing the frequency of feeding. Read your plants - a good deep rich green color means they are happy; washed out, pale foliage means they are likely hungry.
Raised beds may or may not require more feeding, depending upon the depth of the raised layer and the nature of the soil underneath the layer that you added when the beds were constructed.
Containers and straw bales represent the most limited resources for the tomato plants, in terms of water and food. The needed frequent watering means much more leeching of nutrients from the planting mix. My method is to feed weekly with a balanced commercial fertilizer that supplies adequate levels of the three main elements - N (Nitrogen), P (Phosphorous), and K (Potassium), as well as lower levels of trace elements needed for healthy plants.
My plants look healthy, but there are no tomatoes on the plant.
Healthy tomato plants should be producing blossom clusters at regular intervals along the main stem and suckers. A very tall, stretched plant with few flowers can be caused by insufficient hours of direct sun, soil that is nutritionally out of balance (too much nitrogen), or blossom drop - see the following question for details.
I am seeing lots of flowering on my plant, but the flowers are drying up and dropping off, leaving no tomatoes.
Blossom drop is very frustrating to experience. Each tomato variety has conditions that it prefers (temperature, humidity) when it flowers so that pollination occurs and fruit sets. Temperatures that are too low, or, especially with large fruited types, too high impedes pollen flow, hence the ability of the flowers to self pollinate. Typically this is a temporary situation, as eventually the plants will flower in conditions that the plant is happy with to set fruit. It can help to gently flick the opening blossom clusters a few times each day to promote pollen flow.
What are the most common disease problems with tomatoes, and what should I do if I am being impacted by one or more issues?
Tomato diseases are numerous, confusing, frustrating and in many cases fatal for the impacted plant. It is always best, when confronted with a tomato plant issue, to bring infected plant material to a local extension agent or other agricultural professional for a confirmed diagnosis. In a pinch, I’ve found that this site is as good as it gets. The information below is to give you a start at diagnosis, but should not be a substitute for professional assessment.
Here is a brief list of the most commonly experienced tomato disease issues. Fungal issues include Early Blight (alternaria), Septoria leaf spot, Fusarium Wilt, Verticillium wilt, and Anthracnose. The main bacterial issue is Bacterial Wilt, Among the viral issues are Tomato Spotted Wilt, Tobacco Mosaic, and Cucumber Mosaic. Finally, Nematoes can cause significant issues with the tomato roots; they are tiny worms.
Early Blight (alternaria) (fungal) - one of the two most common mostly non-fatal foliage issues, Early blight is a fungus whose spores attach themselves to damp or wet tomato foliage and start causing issues as soon as things heat up. It shows as irregular brown patches on lowest or inner foliage, sometimes surrounded by a yellow zone. It spreads by splashing up from soil (hence the need to mulch), or blows in from elsewhere. It also shows as brown lesions on stems. Some pictures can be found here. Provide adequate spacing of plants so that the sun's rays can hit the foliage all around the plant, and air movement can dry the foliage. Don't water tomatoes from above. Remove lower blemished foliage as soon as you find it to slow the upward spread. There are a host of antifungal sprays (both standard and organic) that can offer help, but must be used according to directions (I do not spray, myself - I remove diseased foliage regularly).
Septoria Leaf Spot (fungal) - impacting plants in the same way as Early Blight, Septoria presents as small brown spots, with yellowing foliage - see some pictures here. Deal with the issue in the same way as Early Blight is dealt with.
Fusarium wilt (fungal) - A fungus that attacks tomatoes through the roots and cuts off water supply to the upper parts of the plant, Fusarium begins to show with overall plant wilt. Very quickly, stems of the plant and foliage turn bright yellow - the plant then typically dies. Once attacked by Fusarium, there is no treatment, and the attack means that the fungus is in the soil in that particular spot. Fusarium can also be seed-borne. Remove the plant and mark the area as one that should not be planted with tomatoes for several years. Here is a picture that shows the impact on the vascular system in the stems. Hybrids with the letter "F", sometimes with following numbers (F1, F2, etc) indicate that the variety has some tolerance or resistance to various races of Fusarium wilt.
Verticillium wilt (fungal) - This disease presents as similar to Fusarium - more information can be found here. It also is a disease that attacks the roots, thus is found in the soil.
Bacterial Wilt (bacterial) - This devastating disease takes down tomatoes quickly, and there is no treatment once the plant is infected. Information can be found here.
Tomato Spotted Wilt (viral) - This disease shows as a coppery, bronzing of upper tomato foliage, followed by wilting - the plant will not be productive and should be removed. It is spread by infected tiny insects called thrips, which chew on the yellow tomato flowers and spread the infection into the plant. Pictures and info can be found here.
There are a number of additional bacterial issues for tomatoes, such as Bacterial Canker, Speck and Spot - information on them can be found here.
Late Blight (fungal) - This is a particularly devastating problem that can take down a tomato garden quickly. Rather than add any more, check out this special site created for discussion of this disease - it includes pictures, descriptions, and maps of its appearance in the US through the years.
Tobacco Mosaic Virus (viral) shows as light and dark green mottling of foliage, as well as finer, more twisted upper foliage. This factsheet covers viral issues of tomatoes.
Cucumber Mosaic Virus (viral) - the main symptom is thread like upper leaves with twisting and thinning - again, refer to this factsheet for coverage of tomato viral issues.
Root Knot Nematodes (tiny worms) - Causing gall like structures on tomato roots, this is another significant issue for some gardeners. Information on diagnosis and steps to deal with the issue can be found here.
What are the most important insect problems with tomatoes, and what should I do if I am being impacted by one or more of these critters?
Aphids are small soft bodied, variably colored insects that gather under foliage or at stem tips in early spring, suck juices and cause leaf curling or plant wilting. The density of the attack - magnitude of the problem - varies season to season, and if they get a good start ahead of ladybugs, can become quite an issue. A few can be killed by squeezing, and lots by using a stream of water. Pictures and information on dealing with them can be found here.
Tomato Hornworms are large (seriously large!) green worms that are voracious - they can ingest significant amounts of tomato foliage quickly. They are not difficult to find when large, as their droppings give them away; their coloring is a pretty effective camouflage, however. Find and destroy them, preferably when they are still small. If they have white pupae on their bodies (which looks like grains of rice), they have a useful wasp parasite that will eat the worm from the inside out after hatching; those worms therefore should be left to remain in place. Much more on this pest can be found here. In general, worm pests can be effectively and safely treated with a biological agent called Bacillus thuringiensis (Bt), as a spray - information can be found here.
Tomato fruitworm is the same as the corn ear worm, and damages tomato plants by chewing foliage, but also by burrowing into and eating tomatoes from the inside, causing loss of fruit. Also controllable using Bt (see the entry above for Hormworm), they can be found when young and hand picked and destroyed, or small tomatoes with the tell tale holes can be sacrificed to destroy the worm eating inside. More info on this pest can be found here.
Stink Bugs are becoming an increasing problem for tomato lovers. The brown marmorated stink bug, in particular, is increasing in population and damage. Stink bugs typically land on tomatoes and suck juices from them, resulting in white spots after the tomatoes ripen. If the population is small, they can be removed by hand and crushed (though the smell of the crushed bug is quite obnoxious). In high populations, physical barriers, such as surrounding the plants with light fabric covering, may be necessary. The insects have complex reproductive systems, making chemical means of eradication not fully effective.
White fly is an annoying problem in which clouds of tiny white insects gather to feed on tomato foliage. They can spread disease and weaken plants when in great numbers. When the population is significant, locations with heavy infestations should be carefully removed from the plant and destroyed.
My plant is wilting - what could be wrong?
Many factors contribute to a wilting tomato plant. It is important to note the color of the foliage - a green wilting plant has something different going on from a yellowing wilted plant. A wilting plant that recovers as night is telling one story, and one that does not recover tells another. It is important to note exactly what is going on - the timing of the wilting and general appearance of the foliage.
Often a plant wilts if it is thirsty; this is true especially with plants grown in containers and straw bales, where the available water to the roots is finite. If the plant is green and healthy and recovers after watering, it is likely fine - be sure to pay closer attention to watering needs, as this is a good way of ending up with tomatoes suffering from blossom end rot.
A wilting plant could also be suffering from herbicide presence; this is particularly true for straw bale grown plants that have green foliage but fail to thrive, often wilting significantly in the heat despite plenty of watering. Be sure to use bales that do not contain persistent herbicides.
Wilting can be an early sign of the onset of a serious tomato disease - please refer to the disease section above for possibilities - particularly if the wilting is accompanied by increasingly yellowing or browning foliage.
My plant is turning yellow and wilting - what could be wrong?
One of two fungal diseases that attack through the roots - Fusarium or Verticillium - lead to foliage yellowing and plant wilting. They are either slowly or quickly fatal to tomato plants, depending upon the concentration of the disease and the particular variety (which may have some resistance or tolerance).
The most important consideration is to understand that the area is infected by the disease spores, so rotation away from the place for future tomato growing is a necessity.
The lower leaves on my plants have brown and/or yellow spots.
Among the many tomato diseases, the two most common attacking agents are the fungi Alternaria (Early Blight), and/or Septoria. Wet foliage attracts spores of either or both, which is why mulching (to prevent soil splash onto lower foliage) is so important. Watering at the plant base, rather than overhead, is also really important to keep tomato foliage as dry as possible.
Though there are a host of anti fungal sprays (both chemical and organic), I've found that excellent and proactive garden hygiene - removal of lower blemished foliage as soon as it shows up - is the best way to stay ahead of these diseases. Significant foliage removal may open the green unripe tomatoes to direct sun, which will result in sun scald. Use newspaper hats or tents to shield the tomatoes from the direct sun.
The foliage on my plants look thin and twisted - what’s going on?
There are two main causes for upper tomato foliage that is wiry or twisted in appearance. Herbicide drift from a neighboring yard, or presence in the soil or straw bales (if that is the technique you are using) will make plants unhappy. Plants could survive a bit of drift, but not significant amounts at the root area.
Viral diseases such as cucumber or tobacco mosaic will lead to mottled an/or thread like foliage. I've had instances where plants survive (but not necessarily thrive) following cucumber mosaic infection, but tobacco mosaic is a more serious issue and plants need to be removed.
What can I do about squirrels?
This is probably the most often asked question during my talks. No matter where I speak, squirrels plague tomato growers.
We've found that providing an alternate food source keeps the squirrels out of our garden. We use a bird feeder that has both seed and suet, with a baffle that keeps the squirrels off of the feeder. The squirrels camp out under the feeder and eat the crumbs dropped by the birds. We also have a birdbath, which the squirrels use for a water source.
Pick tomatoes before full ripeness so that the critters are less attracted to them. Often, the critters are thirsty, and a bite of a ripe tomato slakes their thirst.
If all else fails, it will be necessary to fashion a physical barrier of some sort around your tomato plants.
What can I do about slugs?
Slugs tend to be more of a problem with young seedlings or the tomatoes themselves if plants are allowed to sprawl on the ground. Sprinkling diatomaceouos earth around the plants can be effective.
Saucers of beer are more of an urban legend and not particularly effective.
Iron phosphate and metaldehyde are two substances that are effective against slugs. Do some research before you use them; other forms of wildlife could suffer harm with their use; they are not without toxicity and impact, though under differing conditions they are the methods of choice for slugs.
What can I do about deer?
The absolute only way to guarantee that deer stay out of the garden is a deer fence tall enough so that they can't jump it. This is a costly solution, of course, but for large gardens in heavy deer populated areas, it is really the only way.
I've had good luck with using motion detector sprinklers. As long as I remember to turn on the water and change the battery regularly, they keep the deer out (we live in a very heavy deer area where they are quite tame).
All other remedies may work briefly, but hungry deer will adjust to predator urine, sweaty shirts, hair, dried blood, the various sprays with garlic and/or eggs....rotating different methods frequently may provide some short term protection.
What can I do about birds?
Feed them! Provide a bird bath. Pick the tomatoes before fully ripe - they will finish ripening indoors just fine in a few days. Be sure that your bird feeder and bird bath are an adequate distance from your tomatoes!
If you are feeding the birds and they persist in pecking at your tomatoes, a physical barrier of some sort around your plants will be necessary.
Why are my tomatoes cracking?
Tomatoes can crack radially (moving out from the stem end), or concentrically (circles around the stem). It is a mostly physiological issue, brought on by growing conditions, though varieties can have a slight tendency to crack one way or the other. A large influx of water - through a heavy storm, or infrequent watering - causes the tomato to swell faster than the skin cells can divide to handle the expansion; a crack results. Be sure to pick ripe or near ripe tomatoes in advance of rain; if not completely ripe, they will finish the job just fine on the kitchen counter. Often, splits in the skin will "heal" if they are not too deep. Once deep cracks form, eat them quickly, as they will start rotting from the cracking areas.
What is the brown or black patch on the bottom of some of my tomatoes?
At one time or another, all tomato growers experience the frustration of blossom end rot on their tomatoes. Is your planting medium has a good balance of the nutrients needed for healthy tomatoes (which can be confirmed by sending a sample for testing), the issue is likely due to plant stress. Tomato plants that have set green fruit that visibly wilt in mid day heat are not receiving sufficient water, and development of blossom end rot on the tomatoes is a significant risk. Mulching well, using a soaker hose or drip irrigation, self watering containers, or being vigilant about watering will remedy the problem. Because it is a physiological issue (brought on by conditions, not genetics or disease), tomatoes with blossom end rot that ripen are fine for eating (after cutting away the bad parts, of course) or seed saving.
Much is shared about adding calcium to eliminate blossom end rot. If stress free plants are exhibiting the problem, a lack of calcium is possible, but a pH that is too acidic could be limiting uptake of calcium. A soil test is a good idea to eliminate this possibility.
What are the sunken patches on my ripening tomatoes?
Small round indentations with darker, fuzzy looking centers are a fungal disease called Anthracnose. An excellent reference to refer to, which includes pictures, remedies and ways to avoid the problem, is found here.
Harvest and Seed Saving
Should I let my tomatoes get completely ripe before I pick them?
You certainly can, but they will be much more prone to cracking and attracting critters (birds, squirrels, deer etc) to take a bite before you get to them. Tomatoes ripen from the inside out, so picking them as they start to color, then allowing them to finish on the kitchen counter, will be safer (less cracking, less critter pecking and biting) and develop the vine ripe flavor in just a few days.
Tomatoes that are full sized but drop off the plant when still green can be induced to ripen by storing in a paper bag with a ripening fruit that gives off ethylene, such as a banana or apple. Ethylene stimulates the ripening of tomatoes.
What is the best way to store tomatoes?
Tomatoes will finish ripening perfectly when placed single layer on the kitchen counter. Some articles have been written about the preference of stem end up or down, but I've not noted any great differences of longevity either way. Heirloom tomato varieties in particular are quite perishable and have a short shelf life.
Refrigeration of tomatoes is not recommended due the textural and flavor changes that chilling causes. However, there is nostalgia connected with this storage method; it could very well be that one of your cherished memories is eating tomatoes stored in the fridge after a trip to a local farm stand and loving the flavor. The somewhat stewed, cooked flavor may be exactly what you are seeking to reunite your taste buds with your youthful experiences!
How can I save seeds from my tomatoes?
Tomato seed saving is as simple as cutting a ripe tomato and spreading seeds on an absorbent material and allowing to air dry. Most seed savers add a treatment to the process, such as fermentation or use of a trisodium phosphate (TSP) or bleach solution, occasionally adding a hot water treatment. It is hard to find specific, scientifically based procedures on any of the treatments; much of the info seems anecdotal or home-developed but not optimized.
My preferred method is fermentation, a process which could remove some of the potentially seed-borne diseases from the seeds. Simply (1) cutting an eating-ripe tomato in half and (2) squeezing the seeds and pulp into a labeled water-impermeable cup, (3) adding a bit of water so that it swirls, (4) placing somewhere that the awful smell won't be bothersome (I use the front porch and cover with a paper towel to keep the flies out) for 2-3 days (watching for formation of a white or off white fungal layer), (5) adding water to the cup until nearly full, (6) stirring well, (7) decanting off the non-seed solids (the good seeds sink to the bottom), (8) adding water and stirring and decanting one more time, (9) sieving the now cleaned seeds, (10) scraping onto an unglazed labeled paper plate and spreading into a flat layer, (11) allowing to air dry for a week, (12) crumbling up the seed mass and (13) storing in labeled coin envelopes or vials or other container of your choice is all there is to it. NOTE that during the fermentation process, the gel surrounding the seed is broken down, allowing the germination inhibitor on the seeds to wash away. Allowing fermentation to go longer than a few days will give you a cup of germinating tomato plants!
Use of TSP, bleach and/or hot water is described in various places on the internet, such as here. I cover these treatments as completely as possible in my book Epic Tomatoes.
How should I store the seeds, and how long will they last?
Tomato growers are lucky - unlike onions, peppers and eggplant, to name but a few, tomato seeds have a relatively long life time if kept dry and at a consistent temperature. I've used snap top plastic vials, screw cap glass vials, zip lock plastic baggies and most recently, manila coin envelopes. I keep the seeds in my office in boxes, and experience excellent germination up to 10-12 years. At age 15-16, germination seems to drop to near zero, but I've not done large scale tests.
This is good news, because packets of tomato seed typically contain far more seeds than needed in a particular season. Seed purchased from commercial seed companies indicate the year that it was produced or saved on the packet. You will have a decade or more of use from those seeds.
Tomato seeds stored in the moisture-proof vehicles can be stored in the refrigerator or freezer to extend viability. When planting, be sure to allow the containers to reach the temperature of the room before opening to minimize moisture being drawn in upon opening.
What are your favorite ways to preserve tomatoes?
When the tomato harvest is really kicking in, it can be overwhelming; yet the possibility of having the flavor of summer all year long means that it is a perfect time to preserve whatever you can’t consume. Tomatoes are quite perishable and can pile up in the kitchen quickly.
We’ve found numerous ways to deal with the far-too-short abundance of home-grown, fresh picked tomatoes; canning, freezing, dehydrating, or processing into a food product that can, itself, be canned or frozen, such as salsa, tomato pesto or sauce.
Canning is often shunned because it is thought of as being too much work. In fact, it can be fun, easy, and provide the best reward of all - quart jars of your summer bounty ready for use in fall, winter and spring recipes. Tomatoes don’t need to be peeled prior to canning, and it is a great time to do your seed saving. Recent studies showing the relative equivalence of acid levels among all tomato varieties mean that all of your varieties can be canned together. There simply is no downside.
Freezing is the quickest way to preserve tomatoes but requires sufficient space in the freezer. All that this entails is harvesting perfectly ripe tomatoes (or picking them partially ripe and allowing them to ripen on your kitchen counter). Place the tomatoes in freezer bags, remove as much air as you can, and place them in the freezer...that’s all there is to it. When you wish to use them, let some water run over them (which allows the skin to slip off) and include them in your favorite sauces, stews and cooked tomato recipes. They won’t have sufficient firmness to slice or use as one would fresh raw tomatoes, but all of the flavor will be there.
Smaller tomatoes can be halved and dehydrated, either in a low oven, sun drying outside (being aware of the weather and insects), or using a dehydrator. I like to slow roast tomato chunks drizzled with a bit of olive oil and some pepper and salt until they are a bit leathery but still moist. They freeze beautifully when prepared in this way, and the flavor is intense and addictive.
An overabundance of cherry tomatoes is a perfect entry into a sauce called Trapanese, essentially a cherry tomato pesto. The food processor-made combo of cherry tomatoes, garlic, toasted almonds, fresh basil and a touch of red pepper has to be tasted to be believed, making it one of our favorite pasta sauces….it freezes magnificently as well.
Frequently throughout the tomato season we make big bowls of a pico-type fresh tomato and Jalapeno salsa (buy lots of tortilla chips) - incredible on grilled or roasted fish. Finally, fill a big roasting pan with tomato pieces, sweet pepper, onions, garlic and a splash of olive oil and slow roast in the oven, stirring now and then, until you have the best sauce possible at whatever consistency you desire...be sure to stir in some fresh basil at the very end. Once more, this is a perfect product to freeze or can.