Choosing tomato varieties can be confusing because there are so many, so use our Tomato Chooser to help you pick the best for your garden. Our article “Learn Tomato Terms” explains some basic (but important) tomato terms, such as hybrid, indeterminate vs. determinate, and VFN (disease resistance). It’s a good idea to grow a range of varieties, including at least one or two disease-resistant types, since, of all veggies, tomatoes tend to be the most susceptible to disease.
Soil, Planting, and Care
Tomatoes run on warmth; plant in late spring and early summer except in zone 10, where they are a fall and winter crop. Devote a prime, sunny spot to growing tomatoes. Tomatoes need at least 6 to 8 hours of sun to bring out their best flavours. You will need to stake, trellis, or cage most tomato plants to keep them off the ground. Decide on a support plan before you set out your plants, then add that support directly after planting.
Give each plant enough room to grow. Space robust, long-vined, indeterminate varieties about 3 feet apart. Stockier determinate plants can be grown 2 feet apart. If growing in containers, you’ll need at least a 24-inch pot for an indeterminate variety, or an 18-inch pot for a determinate variety. Tomatoes take up nutrients best when the soil pH ranges from 6.2 to 6.8, and they need a constant supply of major and minor plant nutrients. To provide needed nutrients, mix a continuous-release fertilizer with calcium, like Miracle-Gro® Shake ‘n Feed® Tomato, Fruit & Vegetable Plant Food, into the soil as you prepare the planting holes. (Be sure to read and follow all directions.) This will help protect fruit from blossom end rot, a problem that can occur when the plant isn’t getting enough calcium. At the same time, mix in 3 to 4 inches of compost, which will provide minor nutrients and help hold moisture and fertilizer in the soil until it is needed by the plants.
To grow a really strong tomato plant, we recommend burying two-thirds of the stem when planting. This crucial step will allow the plant to sprout roots along the buried stem, so your plant will be stronger and better able to find water in a drought. Please note that this deep-planting method only works with tomatoes (and tomatillos), not other veggies. Immediately after planting, water seedlings to help settle them in. You can combine fast-maturing varieties with special season-stretching techniques to grow an early crop, but wait until the last frost has passed to plant main-season tomatoes.
Cover the ground with 2 to 4 inches of mulch to minimize weeds and help keep the soil evenly moist. Straw and shredded leaves make great mulches for tomatoes. Water regularly, aiming for at least an inch of moisture per week (through rain or watering), more in the summertime. Feel the soil; if the top inch is dry, it’s time to water.
As summer heats up, some tomatoes have trouble setting fruit. Be patient, and you will start seeing little green tomatoes again when nights begin cooling down. Meanwhile, promptly harvest ripe tomatoes to relieve stressed plants of their heavy burden. If you live in an area in which summertime temperatures are typically in the 90s, be sure to choose some heat-tolerant tomato varieties, bred for their ability to set fruit under high temperatures.
If summer droughts are common in your area, or you tend to forget to water, use soaker hoses, drip irrigation, or other drought-busting techniques to help maintain even soil moisture. Not only will this help prevent cracked fruits, but also help keep blossom end rot at bay. (Moisture fluctuations can reduce the amount of calcium the plant is able to take up, which can lead to blossom end rot.)
Humid weather creates ideal conditions for fungal diseases like early blight, which causes dark spots to first form on lower leaves. Be sure to remove any unhealthy looking or diseased leaves throughout the season. Late blight is a more devastating disease that kills plants quickly; the only way to control it is to protect against it by spraying the leaves with an approved fungicide such as chlorothalonil or copper, and to keep the garden clean of plant debris.
You’ll also want to be on the lookout for pests. In mid-summer, for example, big green caterpillars called tomato hornworms eat tomato foliage and sometimes damage fruits. One or two hornworms can strip a plant leafless in short order! Deal with pests as soon as you spot them.
By late summer, plants that began producing early in the season will show signs of exhaustion. With just a little effort, you can extend the life of those sad tomato plants by pruning away withered leaves and branches. Then follow up with liquid plant food and treatments for leaf diseases or insects, if needed.
Check out our article on Tomato Quirks for more troubleshooting information.
Harvest and Storage
As tomatoes begin to ripen, their colour changes from vibrant medium-green to a lighter shade, with faint pink or yellow blushing. These “breakers,” or mature green tomatoes, can be chopped into salsas, pickled, or pan-fried into a crispy appetizer. Yet tomato flavours become much more complex as the fruits ripen, so you have good reason to wait. The exact signs of ripeness vary with variety, but in general, perfectly ripe tomatoes show deep colour yet still feel firm when gently squeezed.
Store picked tomatoes at room temperature indoors, or in a shady place outside. Never refrigerate tomatoes, because temperatures below 55° cause the precious flavour compounds to break down.
Bumper crops can be frozen, canned, or dried for future use.
Your plant tags say to plant tomatoes deep: two-thirds of the plant underground. Is that really a good practice?
Yes, we recommend this because the more plant you put under the soil, the better the root system. The buried stem of a tomato plant will sprout roots. However, this is not true for all vegetables, only tomatoes and tomatillos.
The tag says full sun, but in Arizona with temperatures reaching over the 100 degree mark, is that going to be an issue with this plant?
We recommend that you give your tomatoes some afternoon shade in summer. They need some relief.
What is meant by "maturity is reached in __ days"?
The maturity is the number of days from planting the seedling until the fruit is ready to pick. This varies a little with weather and region, but the “days to maturity” is a good way to see what will be ready early, mid, and late season.
What size cage should I use for my tomato plants?
Most tomatoes work best with a 5- to 6-foot trellis, stake, or cage. Buy the largest cage possible or make your own from concrete reinforcement wire. The vines of indeterminate tomatoes can get longer than 6 feet, but just let them climb to the top and droop over and down if that doesn’t bother you. Otherwise, you’ll be harvesting with a ladder!
When the plant says full sun, what exactly does that mean?
Full sun means no shade all day, but in many cases in the summer, that’s too much. In hot climates, herbs and some vegetables appreciate a little shade in the mid to late afternoon.
Is it a good idea to always stake or cage my tomatoes?
Yes. Staking tomatoes helps to increase yield and prevent rotting and diseases.
Can I plant one tomato plant in a five-gallon bucket on my patio? How large should the container be for a tomato?
Yes, a 5-gallon container is the minimum size for a tomato plant. A container should be at least 18 inches wide at the top for a tomato, preferably 24 inches for an indeterminate tomato plant. Also, make sure your container has drainage holes.
What do the letters VFFN stand for in the names of your tomatoes?
These letters represent problems that a variety resists, which means that it should not succumb to the problem. V=Verticillium wilt, F and FF=Fusarium wilt races 1 and 2, A= Alternaria leaf spot. The N is for nematode resistance; nematodes are not a disease, they are tiny eel-like pests that ruin roots. There are other designations, too, which are included in the tomato variety descriptions in our online plant catalog.
Is there such a thing as nematode-resistant tomato plants?
Yes, many varieties are resistant to nematodes. Look for the “N” after the name, which stands for nematode resistance. To find these varieties, check the catalog section of our website. Our tomato descriptions list plants’ resistance to nematodes and other problems.
Should I be pruning off the lower branches of my tomato plants? How far off of the ground should the lower branches be?
Pruning is not necessary, but some people do it to keep soil that might harbor diseases from splashing up on the leaves; 12 to 18 inches from the ground ought to do it.
Is it true that pinching off the flowers on the tomato plant helps it to produce more fruit?
It will not help production, but it could increase the size of the tomatoes left on the vine by a little bit.
I just planted my tomatoes and found out that it is too early. Should I put something over them to protect them at night?
Your tomatoes should be okay if you cover them to protect them from frost and cold, strong wind. Don’t let the foliage touch the cover unless it is a material that doesn’t transfer the cold easily, such as bonded polyester row cover, a cardboard box, or a blanket. Avoid metal cans or plastic unless it does not touch the plants.
What causes tomatoes to turn black on the bottom?
They call that blossom end rot. It is thought to be caused by lack of calcium and drought stress. One way to add calcium is to lime the soil. This will help future crops. To help the current crop, purchase a calcium solution, such as Stop-rot, that you spray on the plants.
Do I have to replant tomatoes every year, or do the plants come back when the time is right?
Tomatoes are annuals that are killed by frost. They need to be replanted each year.