Mike Hogan| Special to The Columbus Dispatch
Tomatoes are the rock stars of the summer harvest and this is the time of the growing season when many tomato growers are counting down the days until they harvest lots of ripe fruit. This is also the time of the season when gardeners should be doing everything they can to maximize the productivity of tomato plants in order to harvest bushels of large ripe red (or yellow, purple or multi-colored) beauties.
The water content of a ripe tomato is about 95%, which means that tomato plants will require a minimum of 1½inches of water each week, either from rain or from supplemental irrigation. Tomatoes have deep root systemsand frequent shallow watering, which moistens the top inch or two of soil, will do little to supply the amount of water that tomatoes require. A weekly deep watering that moistens the soil at a depth of 12 to 14 inches will produce more and larger fruit than frequent shallow watering.
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Best wayto grow tomatoes: Consistent soil moisture is critical
A lack of constant and consistent soil moisture can also lead to physiological disorders such as blossom end rot and cracking of the fruit. Blossom end rot is where the bottom of the tomato turns into a blackened sunken canker. It is a symptom of a lack of calcium in the developing fruit that occurs when the soil is not kept consistently moist, preventing the roots of the plant from absorbing calcium present in the soil. Dramatic fluctuations in soil moisture can also cause cracking in the stem end of the fruit.
Be sure to water the soil, not the foliage, in order to keep the foliage dry, which will reduce the potential for spread of fungal spores that cause leaf blights. A 2- to 3-inch layer of organic mulch will also help to retain soil moisture and even out wide swings in soil moisture.
Pruning for productivity
Removing suckers, which are side shoots appearing in the leaf axile between the stem and a leaf, will result in a more open plant, which produces fewer but larger tomatoes, as suckers directly compete with the main stem for water, nutrients, and sunlight.
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In addition to removing suckers, removing the leaves on the lowest 8 to 10 inches of tomato plants will conserve energy for flowering and fruit set, and reduce the possibility of fungal spores splashing onto the foliage of the plants. Leaves can be removed with scissors or pruners, but be sure to disinfect tools with bleach if you see signs of fungal disease such as the yellowing and browning of the lower leaves of the plant.
Continue to fertilize
Tomatoes are heavy feeders of soil nutrients and the abundance and intensity of rain experienced throughout greater Columbus recentlymay have moved some soil nutrients below the root zone of tomato plants.
Be sure to use a fertilizer high in phosphorous, which is responsible for development of extensive root systems and plenty of flowers and fruits. Applying too much nitrogen at this time of the season tends to produce leafy, bushy tomato plants with few flowers or fruit.
Scout for pests
In order to maximize production, be sure to closely inspect tomato plants for the presence of insects and evidence of fungal diseases. At this time of the season, be on the lookout for stinkbugs, aphids, flea beetles, Colorado potato beetle, and spider mites.
In a few weeks, start looking for large tomato hornworms, which can quickly devour the foliage on tomato plants. Evidence of fungal diseases such as yellowing, browningand withering leaves on the lower portion of the plant will require the removal and disposal of the affected foliage. Do not add infected leaves to the compost pile.
Growing large tomatoes
Many gardeners aim to grow the largest tomatoes they can. The key to growing large tomatoes is to select large, indeterminate varieties of tomatoes such as Porterhouse, Rhode Island Giant, Big Zacand Bull’s Heart.Indeterminate tomato varieties are those that do not stop growing when they reach a specific height.They also continue to flower and set fruit for a longer period during the growing season than determinate varieties.
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If you are currently growing large varieties of tomatoes and wish to maximize the size of your tomatoes, remove the new flowers at the top of the plant as older fruit near the bottom of the plant begin to grow. This will force the plant to use its energy to produce fewer but larger tomatoes.
And don’t forget to keep the groundhogs out of your tomatoes, as they tend to feed on the largest fruit just before they are ready to harvest!
More information about growing tomatoes in the home garden can be found at: go.osu.edu/growingtomatoes.
