It's probably no surprise to you that tomatoes are the most commonly grown plant in the vegetable garden. Technically, it's a fruit, but they tend to be treated as a vegetable.
The tomato's origins are as a tropical vine, and we try to make it feel at home as much as possible here in the Rogue Valley. Perhaps our biggest challenge is our cool nights, which make for comfortable sleeping, but tomatoes like their nights warm and humid.
Because the plant must have a certain amount of heat to ripen its fruit, cool nights mean it has to "start over" each morning to acquire those needed hours and days of heat. The amount of heat needed is reflected in the days to maturity listed in your seed catalog or on the plant tab of seedlings you buy.
People often are surprised to learn that tomatoes with excellent flavor are easier to grow in Minnesota, Iowa or other places with high summer humidity than in Oregon. This is a result of the different weather, but plant scientists, including those at Oregon State University, always are working to breed plants that will adapt to local conditions. Several varieties have been developed for the Pacific Northwest that will mature with fewer heat hours, such as Oregon Spring, Siletz, Legend, Medford and the newly released Purple Indigo Rose.
Because we don't live in the tropics, Rogue Valley gardeners must also be mindful of soil temperatures before transplanting tomatoes into the garden. An important tool is a soil thermometer, which should read at least 65 degrees before setting out tomatoes. Soil temperature is very different from air temperature, so do not be fooled into thinking a few days of hot weather will be sufficient to warm the soil. Planting tomatoes in soil that is too cool will encourage blossom end rot, and stunting or failure to thrive.
Before planting, clip off all leaves but a few pairs at the top, and set the plant deep, with the remaining leaves just sticking out of the ground. If your tomato is "leggy," dig a trench and lay the plant on its side. It will straighten itself up, and those hairs on the stem will form roots to help anchor and feed your tomato. Remember to install your tomato cage and watering system at this time.
Fertilizer is not needed when transplanting, although some gardeners swear by putting a spoonful of Epsom salts in the planting hole. Above all, do not give it nitrogen. This results in "all plant and no fruit." Also, too much lush growth simply attracts unwanted insects.
At the suggestion of a fellow Master Gardener, at the end of the tomato-growing season, I will ask you readers to tell me which tomato varieties did well for you and which did not. Please make a note of the date you set your plants out in the garden, whether you used fertilizer, etc. I will share my story, too. It will be fun and interesting to learn from each other about new and old standby varieties, and how our summer weather — always an unknown — affected them.
Coming up: Master Gardener Marjorie Neal will teach a class on growing vegetables and herbs in containers from 7 to 9 p.m. Wednesday, May 30, at the Southern Oregon Research and Extension Center, 569 Hanley Road, Central Point. The cost is $5. For information, call 541-776-7371.
Carol Oneal is a past president of the OSU Jackson County Master Gardeners Association. Email her at firstname.lastname@example.org.