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Top 5 Tips for Growing Tomatoes Indoors

Growing Tomatoes Indoors

Fresh tomatoes year-round? It is possible! We asked a tomato expert for tips on successfully growing tomatoes indoors, no matter how much space you have.

You don't need a backyard garden or a hot and sunny climate to grow delicious tomatoes. To find tips on growing tomatoes indoors, we turned to a tomato expert. Craig LeHoullier (known as the Johnny Appleseed of tomatoes for owning and sharing nearly 5,000 tomato seed varieties) is a gardener, educator, and author of "Epic Tomatoes: How to Select and Grow the Greatest Varieties of All Time." He gave me the inside scoop. If you're lucky and persistent, you can grow and eat tomatoes 12 months a year!

Tip 1: Choose the best tomato variety to grow indoors

First, you can grow tomatoes indoors! But you need to understand what tomato plants need to bear fruit, and it's not just the vines that spin. Choosing the right tomatoes is key to success. For example, Cherokee purple tomatoes can grow up to 15 feet tall. It may not be a happy indoor plant. To be successful with indoor tomatoes, you need short and compact tomato varieties.

LeHoullier recommends dwarfing tomatoes, and starting from seed. LeHoullier says, “Micro dwarf tomatoes grow six inches to a foot tall. You can put a seed and some stock in a pot and it will produce delicious little cherry tomatoes as long as it gets enough light, food and water.

Micro Dwarf Tomatoes are a great seed variety for growing tomatoes indoors, but you may have to search to find them. The Red Robin Micro Dwarf tomato is sold online and produces an impressive number of fruits for its 12-inch height. The secret of a micro dwarf tomato is the small size of the fruit, and the shortness of the plant - perfect for growing on a windowsill and in a small pot. LeHoullier explains that micro dwarf tomatoes can be yellow, orange, purple, or green or red. Fun!

Tip 2: Choose your pot and location for growing indoor tomatoes

For indoor tomato success, you need sun and heat, which is best provided indoors with south-facing windows. Tomatoes need photosynthesis for flavor and flowers to turn into fruits. If conditions are too cold, the tomato plant will grow slowly and develop legs without producing many tomatoes. If you live in an exceptionally cold climate and don't have south-facing windows you may want to invest in some LED grow lights.

For potting indoor tomatoes, LeHoullier says any pot will work, but it should have a drainage hole in the bottom and a saucer to catch the water. He says, “You can use terracotta containers, but they leak water down the sides. Do not use pots that break over time; Your plant will fall on the window."

Tip 3: Choose good quality potting soil and submerged tomatoes

When planting tomato seeds, you need good quality and sterile potting mix. Something like MiracleGro Indoor Potting Mix starts out sterile, so you're not introducing potential diseases to the plant. As with any houseplant, your indoor tomato can get a variety of pests. Watch for aphids and whiteflies, especially with indoor tomatoes.

For feeding indoor tomato plants, LeHoullier recommends a quarter cup per plant per week of a half-strength all-purpose fertilizer. Continued feeding will make the plants produce flowers, which means tomatoes.

How to water indoor tomatoes? According to LeHoullier, “Always water sparingly. The bottom of the pot should have drainage. You can't really let the water out, but tomatoes are unhappy if they're under water.

Tip 4: Rotate indoor tomatoes

Tomato plants tend to bend toward the light, which is a problem when growing tomatoes indoors. To prevent plants from bending legs, turn them 90 degrees every day to help them grow as upright as possible. LeHoullier recommends adding 10-inch plant stakes to the vine, especially once it begins to bear fruit. The weight of the tomato will cause the vine to fall.

If you have an outdoor space, even if it's as small as a fire pit or patio, keeping plants outside during the warmer months will help keep them strong when you bring them indoors in the fall. "When it starts to get frosty, you can bring them inside and let them go indoors," explains LeHoullier.

Tip 5: Eat Your Indoor Tomato!

With a little luck and healthy plants, you can enjoy indoor tomatoes year-round. After flowering on a tomato plant, you should have fruit in about three weeks. What if it didn't happen as fast as you hoped? Don't worry. LeHoullier has grown 4,000 varieties of tomatoes in 40 years, and he says, “Don't take it too seriously. I make mistakes every year!