Tomatoes are the ultimate backyard crop, and growing them is easier than you might think. These tomato growing tips should help you to take care of your most delicious plants.
Why You Should Grow Tomatoes
Here’s a secret. I’d grow a garden just to grow my own tomatoes. Who can blame me? Is there anything better than a fully ripe tomato eaten while it’s still warm from the garden?
Tomatoes annually rank as North America’s #1 home garden crop. No vegetable (technically a fruit) has received more attention from plant breeders and seed savers, which gives us lots of varieties to choose from.
However, you need to read these tips on growing tomatos to start your plants off right and avoid problems before they happen.
10 Tips for Growing Tomatoes
1. Selecting the Right Tomato for You
There are many varieties of tomatoes. Consider these four factors:
Climate and the length of your growing season. If you live in a northern climate, your tomatoes may not even have time to turn red.
Disease-resistance: If you live in temperate climate with lots of moisture or rain, consider blight-resistant tomatoes. Hybrid examples are ‘Iron Lady,’ ‘Defiant’, ‘Mountain Magic,’ ‘Mountain Merit’ and ‘Jasper.’ Heirloom examples are ‘Lemon Drop’, ‘Matt’s Wild Cherry’, and ‘Mr. Stripey’ (also called Tigerella). ‘Jasper’, a tasty red cherry. See our article on avoiding blight with the right tomato.
Type of tomato: How do you plan to enjoy your tomatoes? Beefsteaks are chunky and juicy so great in salads and on burger. Romas, plum, or ‘paste’ tomatoes are excellent for cooking because they contain plenty of flesh for sauces. Cherry tomatoes have the sweetest taste and wonderful for snacks and children. See our post on growing cherry tomatoes!
Growing habits: There are two types of potato plants which require different care.
Determinate or “bush” tomato plants stop growing at about 3 feet tall. The tomatoes ripen within a few weeks of each other, so are great for making sauces for freezing. Bush tomatoes require some support such as a stake and will grow well in containers.
Indeterminate tomato plants will keep on growing and producing fruit until the plant is killed by frost. These plants get quite large and will need some kind of support. Whether you use a trellis, stakes, or cages is up to you, but supporting them is necessary to keep the plants from sprawling on the ground.
Read more about choosing the right tomato variety.
2. Starting Tomatoes Right
Many beginner gardeners start their tomatoes from small plants purchased through an online catalog or at a garden center. If it’s after your frost date, it’s too late to sow tomatoes from seed.
For those who do wish to start tomatoes from seed, especially our northern gardeners who need a head-start on the growing season, it’s vital to provide enough strong, direct light. Many northern gardeners simply do not have strong enough daylight. Learn how to start tomatoes from seed.
Once the seedlings have emerged, it’s very important to use grow lights 14 to 18 hours a day to provide an early boost and promote upright growth. Without enough light, your plants will be spindley and not have a good start to life.
3. Hardening Off Plants
If your seedlings were grown indoors or in a greenhouse, do not just go outside and set them in the ground. Outdoor tomatoes will first need acclimatizing to outside conditions to avoid cold shock. If the plants have been inside a greenhouse, harden them off over a period of two weeks. Begin by leaving plants outside for just a couple of hours a day then gradually increase the length of time they spend outside, avoiding windy days. Bring plants under cover if temperatures threaten to drop below 40 degrees Fahrenheit. Plant outside only after all danger of frost has passed.
4. Preheat Garden Soil and Bury the Stems
Be careful not to plant tomatoes in the ground too soon. They are heat-lovers. Grow your tomatoes on at about 60 to 65 degrees Fahrenheit. Warm the soil with plastic a couple of weeks before you intend to plant.
Two weeks before planting your tomato plants outdoors, dig into soil about 1 foot deep and mix in aged manure or compost. When you do plant potatoes, plant a little deeper than they come in the pot, all the way up to the top few leaves so they can develop stronger roots.
See more on planting tomatoes.
5. Mulching Tomato Plants
Don’t forget to mulch! It helps to conserve moisture and keeps soil-borne disease spores from being splashed up onto the plants. There are many good mulches to choose from—black plastic, straw, shredded leaves, grass clippings, or even a thick layer of newspaper. Oddly enough, red plastic has been found to increase fruiting by 12-20%. Read our Mulching Guide for more information.
6. Remove Bottom Leaves
After your tomato plants reach about 3 feet tall, remove the oldest leaves from the bottom foot of the stem. This reduces fungus problems because the leaves are usually shaded by the rest of the plant and near the soil. Spraying weekly with compost tea also seems to help prevent fungal disease. Learn more about compost tea.
7. Pruning Tomato Plants
To pinch or not to pinch, that is the question. Most gardeners pinch and remove some of the suckers that form between the main stalk and the side branches during the early growth of their plants (the crotch joint). They won’t bear fruit and will take energy away from the rest of the plant.
Note: You definitely do not want to prune determinate varieties or you will have only a few fruit clusters. Since determinates bear fruit only on the ends of their branches, never clip them off, or you won’t get any fruit at all!
But just how much should you prune them, if at all? Pruned plants bear earlier and have larger tomatoes, but they also have fewer tomatoes. Overpruning can cause sunscald—a yellow sunburned patch that eventually blisters. Unpruned plants yield about twice as much fruit as pruned ones do, but it will take longer for the fruit to ripen. Pruning also affects flavor. The more foliage a plant has, the more photosynthesis is taking place, which produces more sugars in the fruit. The excess foliage shades the fruit and insulates it from summer heat, making it ripen more slowly and improving the taste.
Of course, if the foliage on your plants is so thick that no fresh air can reach the center of the plant, then by all means, pinch off a few suckers. If your indeterminates are reaching for the stars, you can top them above the highest blossoms to keep them in bounds and encourage green fruit to ripen.
8. Watering Tomato Plants: How Much is Enough?
Tomato plants need 1 to 2 inches of water per week. Uneven watering can set the stage for blossom-end rot and may also cause fruits to crack open. Stressed plants remove calcium from the fruit and send it to the shoots to keep the plant growing. Along with uneven moisture, excessive nitrogen and high soil acidity contribute to blossom-end rot.
9. Feeding Tomato Plants
Most gardeners have a secret or two up their sleeves. One man I know treats his plants to crushed eggshells in the planting hole, another uses a handful of bonemeal, and someone else swears by a pinch of Epsom salts. If you must fertilize, side-dress the plants with compost or a dose of liquid seaweed or fish emulsion. Stay away from high nitrogen fertilizers unless your plants have yellow leaves. Too much nitrogen will cause lush foliage growth but give you little or no fruit. If the leaves on your plant are purple, they are calling for more phosphorus. This is the most important nutrient for fruit production.
10. Troubleshoot Tomato Problems
Tomatoes will attract pest and disease but if you keep your eye out for them, you can avoid many problems.
Learn more about tomato diseases and disorders.
See how to troubleshoot tomato problems.
If all this advice seems daunting, take heart: Tomatoes are really one of the easiest vegetables to grow, and even the worst home-grown tomato tastes better than a store-bought one.
See everything you need to know about planting, growing, and harvesting tomatoes in the Almanac’s complete Tomato Growing Guide.