FEATURE – Tomatoes are the most popular garden crop, and for good reason.

Varieties – determinate and indeterminate

Determinate varieties set on, then stop growing vines. Indeterminate vines never stop growing until they freeze in the fall.

Temperature facts

Tomatoes will not set on if the nighttime temperature falls below 55 degrees or if the daytime temperature gets above 95 degrees. Knowledgeable gardeners do not bother with shading, but tomatoes will thank you for afternoon shade. Cherry tomatoes will set on better than any regular varieties in temperatures over 95 degrees.

Fertilizer magic

Most gardeners under-fertilize their tomatoes. Tomatoes don’t need a lot of nitrogen, but you should err on the side of too much. And the more phosphate you can get into the plant, the more and bigger tomatoes you will harvest.

Monoammoniumphosphate is a water soluble fertilizer of 11-55-0, or something close to that depending on the manufacturer.  Miracle Gro is an excellent water soluble fertilizer, but is more expensive.

Other Tips

• Consistent soil moisture will help prevent cracking of the tomato; covering the ground around the tomato plants with straw or grass clippings will help keep the ground moist and keep weeds under control
• Tomatoes will get “sunburn” when exposed to hot afternoon sun; these whitish blemishes can be minimized by providing afternoon shade, or by covering tomatoes with light sunscreen netting
• You will get a better and consistent flavor by picking tomatoes as soon as they turn red, then allow them to fully ripen a day or two on the counter
• Tomatoes that touch the ground will become scarred and vulnerable to bugs, worms, and rot
  • Keep determinate tomatoes off the ground with trellising and staking
  • Let indeterminate varieties run, don’t stake them but make sure you place some barrier between the ground and your ripening tomatoes; slmost anything will work as a barrier, newspaper, straw, sawdust, things that compost, not plastic

Sunlight and spacing

Leaves will turn yellow and die on any plant whose under-leaves become too shaded and then it becomes restricted in its production. Determinate tomatoes should be planted 2 to 3 feet apart. “Caging” opens the plant up to sunlight, keeping the leaves from yellowing.

Indeterminate varieties should be planted about 4 feet apart and can be allowed to “run” on the ground as long as you provide the barrier mentioned above.

Bugs and pesticides

There are only two pests you need be concerned about with tomatoes, the beet leafhopper, which spreads the curlytop virus, and tomato hornworms.

The leafhopper is difficult to deal with, but spraying your tomato vines with a powdered milk mixture (one pint of powder to one gallon of water) is as effective as anything. Just spray your tomatoes about every two weeks—after the hills lose their green color (more often if rain washes off the milk). All you’re trying to do is keep a whitish color on your tomatoes. Don’t laugh, it works.

Hornworms is an easy battle to win—and it takes no pesticides to do it. The tomato hornworm begins too small to really see, but as they grow, they will eat off leaves, tender stems, and chew into tomatoes, stripping your tomato plant of its foliage. Obviously, this is not good. Put on a pair of gloves, and visually examine your tomatoes regularly. Early morning is the best time to find the worms near the tops of your vines, where they are easy to see. As the day warms, the worms retreat down to where it is cooler. What you look for are missing leaves, stripped branches, and small dark droppings on the ground and in the forks of branches; then look for the hornworms. They will be from about one inch to four inches long. Pick off the worms by hand and destroy them.

See more of Rex’s Tips on how to grow great tomatoes here.

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Copyright 2012 St. George News.