How to Plant Tomatoes

Plant your tomatoes the right way, and you’ll have a bigger harvest, plus fewer pests and problems to contend with throughout the season. Here’s what you need to know to tackle the job like a pro.

Start With Small Tomato Plants.

If you’re buying your tomato plants, choose short, healthy-looking plants. If you’re growing your own from seed, start them six weeks before the average last frost date for your area, so they don’t have a chance to get too tall before you transplant them. Plants that grow tall while they’re in their seed pots tend to have weak root systems. You want your tomatoes to do most of their rooting when they’re in the ground and have lots of room to spread out.

Choose the Right Spot.

Tomatoes need at least eight hours of direct sun each day to do well. In northern states, they need near continuous sunlight to do well, but in southern states, tomatoes actually benefit from receiving some shade in the afternoon. It helps them to cope with the heat. If it gets too hot (above 90 degrees), they’ll stop producing temporarily. That being said, be sure to choose a spot that receives full sun in the morning. Tomato plants need that early sun to dry the dew off their leaves, so they don’t succumb to disease.

Plant your tomatoes in late spring, after the last risk of frost has passed. Tomatoes can’t take the cold.

Bury Your Tomatoes Deep.

Most plants should be planted even with the soil line in their pot, but that’s not the case with tomatoes. They need to be planted much much deeper. If you want your tomatoes to do well, you should actually bury two-thirds of the plant. This will leave just the top few leaves showing above the soil. And while that may seem crazy, it really is the very best thing you can do for your tomatoes. Roots will grow all along the buried stem, resulting in a much stronger root system, which means more nutrient and water uptake for your plants. And that ultimately translates into more fruit and better heat tolerance.

Another good reason to plant your tomatoes deep? With less plant sticking up above the ground, you won’t have to worry about those strong spring winds snapping your young tomato stems.

Get the Spacing Right.

Plant your tomatoes two feet apart from each other, so there will be plenty of room for air to circulate. This will help to keep diseases at bay, and ensure that your plants get plenty of sunlight. If you’re planting your tomatoes in a square foot garden, plant one per square.

Pro Tip: Plant your tomatoes on an overcast day, so they’ll have time to acclimate before being exposed to lots of sun and heat.

Stake Your Tomato Plants.

Stake or cage your tomato plants as soon as you plant them. If you wait for them to get big, you risk damaging their roots. Determinate bush varieties of tomatoes may not need to be staked or caged, but indeterminate varieties definitely need to be.

Water Consistently.

Water your tomatoes deeply when you plant them. Then, continue to water them deeply and regularly throughout the growing season. Consistent watering helps to prevent blossom end rot and cracking, which occurs when you allow the soil to dry out between waterings. Tomatoes need an inch of rain each week, so be prepared to step in when Mother Nature falls behind. But avoid watering in the evening. Wet leaves encourage fungal growth. For this reason, it’s also important to water the base of the plants, and not the foliage.

Once the soil has warmed for the season, mulch around your plants to help with water retention and prevent soil splash (a common cause of fungus).

Prune Your Tomato Plants.

Once your tomato plants are two or three feet tall, remove the leaves and suckers from the bottom foot of each plant. If you’re not familiar with suckers, they’re the little branches that form between the main stem and an existing branch. These will grow into full-size stems, if left in place; and you don’t want any stems or leaves touching the ground, where they could pick up a fungal disease from the soil. This early pruning also serves to improve air circulation around the base of the plants, so fungus is less likely to take hold.

Some gardeners continue to pinch off tomato suckers throughout the growing season because they believe they take energy away from the main plant. Others leave them because they feel they contribute to a larger harvest. You’ll be in good company, no matter which side you choose.

Fertilize Your Tomatoes Regularly.

Tomatoes plants are heavy feeders. Fertilize your tomatoes when you plant them. Then, fertilize them again when they set fruit. Continue to fertilize your plants regularly throughout the season. A balanced fertilizer is best. Adding crushed egg shells to the soil will provide a calcium boost, and help to prevent blossom end rot.

If your tomato plants have lots of leaves and little fruit, add more phosphorous.

Companion Plants for Tomatoes

Increase your harvest, and make caring for your tomatoes easier, by planting them next to beneficial plants. Here are some winning combinations to try.

To Deter Pests, Plant Your Tomatoes With …

• chives, onions, garlic, leeks or shallots (they’ll repel aphids and other pests)
• nasturitums (they’ll repel aphids and whitefly)
• borage, marigolds or petunias (they’ll repel hornworm)
• asparagus (it’ll repel nematodes)
• borage (it’ll increase disease resistance)

To Attract Pollinators, Plant Your Tomatoes With …

• basil
• mint
• bee balm
• borage

To Improve Growth and Flavor, Plant Your Tomatoes With …

• basil
• parsley
• chives
• mint
• bee balm
• borage (it’s a good source of calcium, so it’ll help with blossom end rot)

All of the above companions will also serve to shade the soil, keeping it cooler and minimizing evaporation.

Do Not Plant Tomatoes With …

• potatoes, eggplant and peppers (they’re in the same family, so they’ll build up blight in the soil)
• corn (it attracts similar pests)
• dill (when mature), kohlrabi, fennel, broccoli, cauliflower, cabbage and other members of the brassica family, (they’ll inhibit growth)

How Many Tomatoes Should I Plant?

Under the right growing conditions you can expect to get around 25 pounds of tomatoes per plant. Plan on 2-4 plants for each person in your household. Increase this number, if you intend to do a bunch of freezing and canning.