Caring for Tomatoes

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Tomatoes are the most popular summer vegetable grown in gardens. Whether your tomatoes are in the ground or still waiting to be planted, you can follow these tips for tasty tomatoes all season.

Soil preparation. Tomatoes prefer a soil pH of 6.5 to 6.7. Adding lime to reach this point is key to preventing problems like blossom end rot and nutritional deficiencies. Lime takes months to begin taking effect.

Planting. If plants are tall and leggy, dig a small trench and lay the tomato plant in sideways, so only the top few leaves are above ground. The plants will develop roots at the nodes where the leaves were.

Watering. Tomatoes perform best when soil is not allowed to dry out or remain wet. Plants need about 1.5 inches of water per week.

Picture of tomato with blossom end rot

When growing tomatoes, strive to keep soil consistently moist. Extreme changes in soil moisture contribute to blossom end rot, pictured here. Courtesy of Wikimedia Commons by A13ean

Allowing soil moisture to fluctuate too much will result in blossom end rot, a disorder characterized by black leathery spots on the blossom end of the tomato. Soaker hoses are superior to sprinklers, because they keep water off of leaves.

Rotating. Tomatoes should not be planted where they were grown last year. Rotating vegetable crops will help to prevent the build-up of pathogens, like those that cause early blight, in the soil.

Fertilizing. Tomatoes are very sensitive to over-fertilization. Tomatoes should be fertilized after plants have started to set fruit and 4 to 6 weeks thereafter during the season. Plants should be side-dressed with 2 to 3 tablespoons per plant of a complete fertilizer such as 8-8-8 or 10-10-10. The fertilizer should be applied 4 to 6 inches from the plant stem to avoid fertilizer burn.

Mulching. Mulching around plants will help to maintain even soil moisture, prevent weeds, and slow some diseases. To mulch, lay a 2 to 3” layer of straw or composted leaves around the plants.

Staking. Unless you’re growing bush tomato plants, you’ll need to provide some support for stems of tomato plants. There are many systems, including wooden stakes, tee-pees, and tomato cages. The important thing is to keep stems off of the ground.

If you run into trouble with your tomatoes, contact the Caldwell County Cooperative Extension Service at 828-757-1290.