Provide tomatoes with nutritious soil, sunshine and plenty of water to reap an abundant harvest.
While genetics, gardening skills and Mother Nature play major roles in the quality of tomatoes, the trick to harvesting succulent, sun-kissed tomatoes is to grow thriving, vigorous plants with deep, nutrient-seeking roots and foliage that captures the blazing summer sun. Providing loving care to a tomato plant from its seedling start to its fruited finish yields a ripe, fresh, delicious reward. That TLC centers on providing the tomato plant with what it needs to thrive and nurturing it as it grows.
Whether you’re a seasoned or a beginning garderner, we’ve provided a guide to growing tomato plants with some quick lessons in basic tomato care to inspire your journey as you capture the taste of summer in your garden.
Provide Soil and Sunshine
Once hatched and sprouted from their tiny seed cocoons, tomatoes aren’t difficult to grow—as long as they receive some basic necessities. Like many cultivars, tomato plants require nutrient-dense, well-draining soil and plenty of sunshine to thrive, says David Trinklein, associate professor and floriculture state specialist with the division of plant sciences at University of Missouri Extension in Columbia, Mo.
In the early spring—well before your region’s planting season—take a close look at the soil quality and sunlight exposure in the area where you plan to stake your tomatoes, and consider the following.
Test your garden soil’s pH and nutrient levels with a commercial test kit. If it indicates a need for pH-boosting lime, which provides calcium and magnesium to growing plants, mix some in along with the appropriate amendments to correct phosphorous, potassium or other nutritional deficiencies.
Your soil’s texture matters. Light, sandy soil retains too little water, and heavy, clay soil holds too much. Well-drained, loamy soil is just right. Compost or rotted manure can create the ideal soil texture and nutrient density that tomato plants require. Tomato plants grow well in many types of soil, but they do best in a nearly neutral soil with a pH of 6.5 to 7.0.
“You can improve garden soil by adding organic matter such as peat moss, leaf mold, well-rotted manure or compost. Work the soil only when it is dry enough, so it doesn’t stick to tools,” Trinklein says.
Tomato plants require plenty of sunshine, so choose a south-facing spot in your garden where they’ll soak in at least six hours of bright sunshine.
“Tomatoes grow best when they receive full sunshine,” Trinklein says. “Plant tomato plants away from trees and buildings to get the highest yield. A tomato plant needs a lot of water, so arrange for easy watering. Select a well-drained area, as poor soil aeration leads to root loss and physiological problems, such as blossom-end rot.”
As the days grow longer and the soil temperature in your vegetable garden reaches a balmy 60 to 65 degrees F, it’s time to move your 6- to 10-inch tomatoes from their indoor home to their outdoor home. Before that, you’ll need to harden them off. This means gradually acclimating the starts to their new environment without damaging or shocking them, says Alan McDaniel, cooperative extension specialist with Virginia Polytechnic Institute and State University’s horticulture department in Blacksburg, Va.
“A few weeks before transplanting time, harden off indoor-grown tomato plants by exposing them to an increasing number of hours outdoors each day,” he says. “Bring the tomato plants in if there is danger of frost.”
Once your starts are ready for what Mother Nature has to offer, measure out your plant rows and spacing, and set out the starts, making sure to provide enough room. In general, staked, caged or trained tomato plants need a 3- by-3-foot space; sprawling or bushing tomato plants need a 4- by 4-foot space. Your rows should be 4 to 5 feet apart.
Proper spacing and staking are essential for healthy tomato plants and good fruit production.
“Your planting distance depends on the type of tomato grown, but ideal spacing for home-garden tomatoes is generally
24 to 36 inches between plants," Trinklein says. "Planting closer than 24 inches reduces air circulation around the plants and can trigger disease outbreaks.”
Next, dig holes with a hand trowel, remove the tomato transplants from their pots, and set them in the ground so that only two or three sets of true leaves are exposed. If necessary, place the tomato plant horizontally in the hole so that much of the stem is buried.
“Horizontal planting offers an effective way to make plants, especially leggy ones, grow stronger,” McDaniel says. “Roots form along the buried portion of the stem, giving better growth and a reduced chance of plant injury from a too-weak stem.” If your starts are in peat or paper pots, you can plant them just as they are, but open or tear off one or two sides to give the roots a running start, he suggests.
Once the tomato transplants are in place, press soil firmly around each one so a slight depression forms for holding water, and pour about a pint of starter solution or diluted fish emulsion around each plant to wash the soil around the roots, McDaniel says.
Support the Sprawl
The final step to giving your tomatoes a home sweet home: training or adding support before the plants start to sprawl. This process trains tomatoes to grow upward in a cage or along a stake.
“Trained tomato plants have better air circulation and keep the leaves less susceptible to disease attack,” says B. Rosie Lerner, horticulturalist with Purdue University’s cooperative extension service in West Lafayette, Ind. “Fruits are held off of the soil, which helps prevent diseases, and the plants can be spaced more closely to allow greater production.”
A familiar sight in the vegetable garden, a wire tomato cage is made of heavy-duty wire and surrounds a tomato plant and supports its branches and fruits as they grow. Useful for determinate and indeterminate varieties, tomato cages have definite benefits.
“Caged tomatoes tend to be more productive since suckers do not need to be removed,” Lerner says. “They are also less prone to sun-scalding injury because the suckers provide greater cover for foliage.”
You can find commercial tomato cages at a local garden-supply store, or you can make your own with a 5-foot-tall by 4-foot-diameter cylinder of open-weave fencing.
"[If you create your own tomato cage,] make sure that the mesh is wide enough to allow your hand to reach in and harvest the tomato—preferably 6 by 6 inches,” Lerner advises. “Pay attention to the mature size of the tomato cultivar you’re growing. The tomato plants might start out small, but they can soon outgrow a small cage.”
Staking tomatoes also provides support to the tomato plants via a sturdy 1-inch-diameter pole that runs up the plant’s main stem. To stake your tomato plant, set an 8-foot length of pole 1 to 2 feet deep and about 4 inches from the young plant. As the tomato grows, use soft cord or strips of cloth to secure the stem to the stake.
To keep the plant trained to grow up the stake, you must remove the suckers, Lerner says.
“Suckers are the side branches that form in the axils of the plants: the points where the leaves join the stem,” she says. “Check the tomato plants at least once a week for sucker development, and pinch out the growing tip of the sucker just beyond the first two leaves on the branch. Allowing the first two leaves to remain gives the plant better foliage cover, which protects the tomatoes from sunscald.”
Whether you cage or stake your tomato plants, put the structures in place when the plants are young to prevent injury to their root systems.
With the sun shining and the tomato plants happily in place and growing like wild, your main vegetable garden chores through the summer will include watering, mulching, fertilizing and foliage control.
Tomatoes need 1 to 2 inches of water per week to maintain their health and churn out juicy, top-quality fruit. To keep the soil moist, consider adding a layer of organic mulch such as straw, hay or bark chips. Mulch prevents evaporation and moisture-level extremes, and it keeps weeds from germinating.
“Apply 2 to 4 inches of organic mulch after the soil has had a chance to warm up—usually by June,” Lerner says.
Along with deep yet infrequent watering, vigorously growing tomatoes love rich, fertile soil. In addition to blending fertilizer into your soil when you prepare your vegetable garden, you should plan to side-dress your tomato plants during the summer.
A noninvasive method of feeding tomato plants, side-dressing involves applying fertilizer—nitrogen-rich for flowering or balanced for overall growth—such as compost, worm castings or manure tea in a circle around each plant or in a double line down your rows, says Robert Dufault, professor of horticulture at Coastal Research and Education Center in Charleston, S.C.
“Tomatoes are heavy feeders,” Dufault says. “Use a starter solution for transplants, and side-dress when the first fruits are about the size of quarters, using 1½ ounces of 33-0-0 fertilizer (33 percent nitrogen; the rest is inert material) per 10 feet of row. Side-dress again two weeks after the first ripe tomato with a balanced fertilizer such as 5-10-5 (5 percent nitrogen, 5 percent phosphate, 5 percent potash), and repeat this step one month later.”
Finally, foliage control involves pinching or pruning out-of-control leafy growth on your tomatoes. Although those leaves are critical for turning sunshine into energy for your growing plants, they also can shade the tomatoes and cause slow ripening in autumn.
“Though determinate and semi-determinate varieties typically don’t require pruning, indeterminate or large-vine varieties benefit from the removal of some of their axillary or side shoots,” Trinklein says. “They also can be topped to prevent tomato plants from becoming too bushy and tall. When pruning or topping, break out only enough shoots to allow good light and air movement throughout the tomato cage.”
Harvesting and Enjoying Tomatoes
During a busy summer and autumn, your big, glorious globes of tasty tomato goodness will ripen and be ready to enjoy. If you can resist picking them, let your tomatoes ripen right on the vine for optimal taste.
“Harvest tomatoes when they’re fully vine-ripened but still firm,” McDaniel says.
You also can pick the tomatoes when they’re pink and allow them to fully ripen off of the plant, particularly if the weather forecast includes rain or frost.
“Ripe tomatoes are more susceptible to sunscald and skin cracking so you can pick the fruits and place them in a warm, shaded location or even in the dark to ripen,” Lerner says. “Light isn’t necessary for further ripening. Most picked green tomatoes will ripen to a red color if placed in a dark, warm, 65- to 70-degree-F location.”
Enjoy your beefsteak, slicers, cherry and grape tomatoes when they’re at the peak of ripeness; make delicious tomato-based dishes with your ripe fruit; and preserve whatever you have left over for the dreary dregs of winter. Make sure to can and dehydrate enough to share, because when it comes to these delicious summer fruits, you can never have too many!
Excerpt from Tasty Tomatoes, part of the Popular Gardening Series, with permission from its publisher, BowTie, Inc. Purchase Tasty Tomatoes here.