I like growing tomatoes in a greenhouse though many varieties do well outside here in Southeast Alaska. Tomatoes prefer their roots and air temperature to be relatively the same, between 65-75 degrees. Good ventilation not only keeps mold and disease down but also helps pollinate. Use a fan, windows and/or doors. It’s a good idea to pollinate by hand once a week or so just to be certain. Just go along and tap the stem so the plant shakes a bit, or just hold the plant and give it a little shake. The best time to pollinate is early afternoon when the sun is out. Cat-facing, or scarring on the bottoms of the tomatoes, is often caused by poor pollination.
Tomato plants thrive on more calcium than other plants, so I like to add coffee grounds and eggshells to their soil periodically. However, keep in mind that the plants also need magnesium sulfate (Epsom salts) to use that calcium. You can add some to their water or do a foliar spray every so often using ¼ tsp. salt to a quart of water. If you notice the leaves start turning a purplish brown color, this could mean they need more magnesium sulfate. If you find the leaves turning dark green, curling, and you are getting more leaves than fruit, your plants might be getting too much calcium.
Make sure your plants get plenty of water. Better to give too much water than not enough. If your plants wilt, it could cause blossom end rot and buds to drop. If your plants are getting enough water but still wilt, it might be because they are too hot. Just gently mist them with cool water if this happens.
One last piece of advice. If you sucker your plants, the plants will have more energy to put into fruit rather than growing suckers. Suckers are the little shoots that grow in the “v” between the branch and the main stem.
– Francis Leak owns Chilkat Valley Farms