This spring's lower-than-normal temperatures stressed tomatoes in familiar ways.

A truly warm-season crop, plants took hold late and barely grew at all until the second half of June. Fewer insects were busy, and the few flowers that opened were poorly pollinated, especially when the plants were enveloped by hotcaps or walls-o'-water.

By now, tomato harvest should be in full swing. But this summer, many gardeners are still waiting and worrying about fruit that's disfigured or rotten. Patience will pay off soon with healthier tomato fruit, so long as gardeners planted in well-drained soil and maintain consistent soil moisture.

Blossom-end rot (BER) is very common on tomatoes that form during chilly, cloudy weather, drought, extended flooding, or at the time of transplanting. These seemingly unrelated conditions have one thing in common: less water and nutrients moving from roots into leaves and flowers. As weather conditions improve, so do the fruit.

Catfacing is another common disfigurement of tomatoes linked to cool spring weather. Luckily, it doesn't affect fruits' edibility. Slicing these quirky fruits is more like carving practice, but the homegrown taste is worth the extra effort.

Tomato fruit can be harvested 55 to 90 days after transplant, depending on variety, when conditions are right. With the average last frost around mid-May, Utah gardeners are usually picking ripe tomatoes by mid-July. This year, many gardeners watch and wonder.

Tomatoes grow best in soil that is consistently moist and aerated. In Utah, raised beds are a good strategy. Elevated 6 to 12 inches above grade, soil near tomato roots drains fairly quickly, allowing air to fill the larger soil pores. Organic matter amendments and a layer of organic mulch help conserve soil moisture. Plant roots stay rot-free but have nearly constant access to water; a best of both worlds.

Tomatoes are the most popular home garden crop in the U.S.; 93 percent of gardeners grow them. Yet they are far from the easiest crop to produce, even with the improved, disease-resistant hybrid transplants that are most commonly available in spring.

Most Utah gardeners see few insect pests, although the tomato hornworm can decimate foliage within a few days. Diseases such as bacterial speck, early blight and curly top virus are fairly common but seem to affect certain locales differently from year to year. The more common diseases of tomato are caused by environmental stress: chilling temperatures, drought, poorly drained soil, salty soil, poor nutrition, etc.

Few vegetable crops could survive naturally in Utah. For better harvests, gardeners amend native soil with extra organic matter. In theory, this is wise and right, but amendments like manures are often high in salts and can stunt plant growth and cause droughtlike symptoms. Send a soil sample for analysis to help diagnose plant problems. (Visit the USU Analytical Lab Web site at www.usual.usu.edu for soil test instructions and order forms.)

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Maggie Wolf is a horticulturist in the Salt Lake City area. E-mail her at gardenutahconsult@gmail.com.