Avoid These Common Mistakes When Growing Tomatoes - Backyard Boss
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Avoid These Common Mistakes When Growing Tomatoes

Tomatoes come in countless fun varieties, brighten up a summer garden with their vivid red hue, and are edible right off the vine–it’s no wonder they’re so popular with home gardeners. 

These fruits generally have a high success rate. But to make the most of them, there are a few tips and tricks to keep in mind. 

Choosing the wrong tomatoes

Tomatoes on vine
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There are two major categories of tomatoes to consider: determinate and indeterminate. The type you choose should depend on the amount of garden space you have and on your culinary ambitions. Do you want a single bumper crop or a whole summer of fresh pasta sauces?

Gardeners with limited space generally prefer to grow determinate tomatoes. These plants will max out around three feet tall, and the fruits will ripen all at once.

Indeterminate tomatoes, which include popular varieties such as heirlooms and cherries, are a slightly more ambitious undertaking–they will continue to grow and produce fruit throughout the whole summer, dying off only once the first frost hits. These plants can reach up to 20 feet depending on the breed, so you’ll need to keep an eye on the heavy vines and upgrade your support structures as needed.

Within these two categories, there are other factors to consider. Some varieties are more resistant to pests and diseases than others. Some grow into bushes, while others grow on long, snaking vines. Make sure you know what to expect and have the right supports, such as stakes and ties, on hand.

Not providing enough light for seedlings

Tomato seedlings
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Many gardeners sow their tomato seeds indoors in late winter. If you live in a region that experiences short winter days, your young tomatoes may struggle to get enough light. 

Place your seedlings in the sunniest part of your house, and turn the tray regularly. If the stems continue to look flimsy, try investing in an LED grow light to supplement the sun’s rays. 

Planting tomatoes outside too early

Snow on grass
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You might be tempted to get a head start and transplant your tomato seedlings outdoors as soon as the weather turns springlike. But as a general rule of thumb, you shouldn’t plant tomatoes until daytime temperatures hit at least 60 degrees.

Keep your seedlings indoors until they are six inches tall with strong, upright stems. (Don’t wait too long past this point, as the seedlings risk becoming rootbound or stunting one another.) When the seedlings are almost ready, give them a chance to acclimatize to outdoor conditions by letting them sit outside, still in their trays, for a few hours each day.

Tomatoes are heat- and light-loving plants and can suffer during cold nights, producing fruit that is small or misshapen. In a worst-case scenario, the plants may fail altogether to produce fruit.

Crowding tomatoes

Tomato vines
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Pay attention to the spacing advice on your tomato seed packet! It may seem excessive at first, but tomato plants need plenty of space between them for airflow. Plants that are too close together also run the risk of creating too much shade.

Exact spacing requirements vary per tomato type, so make sure you follow advice specific to the breed you’re growing.

Overwatering tomatoes

Watering tomatoes
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If you’re anxious about your tomato plants succeeding, you may want to water them daily. But drowning your tomatoes can do just as much harm as parching them.

The amount of water your tomatoes need depends on the variety you’re growing. Most tomatoes like one to two inches of water per week. But rather than shallow daily waterings, which can cause diseases to breed, give the soil a good soak once or twice a week, allowing it to dry out in between waterings.

Water the base of the plants instead of soaking the leaves from above, and avoid watering tomatoes when the sun is at its peak. This can cause the water to dry up before the tomatoes’ roots have had a chance to absorb it.

Not making use of companion plants

Tomatoes and garlic
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Companion planting is the practice of growing certain species in proximity, allowing them to form positive symbiotic relationships.

Several common vegetable garden plants can help your tomatoes thrive. Carrots loosen the soil near tomatoes. Garlic repels the spider mite, a common tomato pest. Planting lettuce under tomato plants helps cool and moisten the soil. Basil intensifies the flavor of tomatoes, enhances their growth, and repels harmful flies.

Be careful when companion planting, as some species can harm tomatoes when planted nearby.

In summary

With just a bit of planning, growing tomatoes can make for a fun and relaxing summer project. By avoiding these pitfalls, you’ll be rewarded with a bounty of healthy, plump fruit that will take your Caprese salad to the next level.

Let us know which mistakes you used to make, and as always, please share!