San Francisco Chronicle - (Sunday)
10 steps to growing Bay Area tomatoes.
Spring is that time of year when the gardener’s fancy turns to tomatoes. Not every Bay Area garden will ripen this coveted fruit, but many will, and the following tips will give you the best shot at success.
1. Choose a variety suited for your microclimate. In much of the Bay Area, summer nights are cool, their chill inhibiting fruit set. Nearest the coast, summer days are also cool, slowing growth. But throughout the entire Bay Area, the frostfree period is long. For these climatic conditions, our best bets are tall, or indeterminate, varieties, as they will keep growing into fall and thus have many opportunities to set fruit. Nearest the coast, start with cherry or other smallfruited varieties, since they have more flowers and therefore more chances for fruit set. Also choose early varieties, meaning 5070 days to harvest (DTH); this is calculated from the day you plant the seedling. In somewhat warmer areas, such as the milder parts of San Francisco and cooler parts of the East Bay, try midseason varieties, 7080 DTH; inland, late varieties, 80+ DTH, should thrive.
2. Choose a variety that resists diseases you are likely to see. Look for capitalletter codes after variety names to show resistance. Near the coast, late blight (LB) and verticillium wilt (V) are common. Inland gardeners are more likely to see fusarium wilt (F).
3. Choose the best site. Where summers are cool, site your tomatoes in your sunniest, least windy location. Where summers are always hot, plant where they will get some afternoon shade. It isn’t your address that determines if tomatoes will thrive but the specific conditions of your garden. A site with wind protection and allday sun may work. Down the block, wind may blow heat away from another sunny garden, preventing success.
4. Plant deeply, with good stuff at the bottom of the hole. Dig a hole a foot or so deep. Put in a shovelful of good compost, or compost mixed with aged manure or worm castings. Add an inch layer of soil on top, then plant above this. If you are planting in a container, no need to add organic materials at the bottom, just grow in container mix. Plant fullsize tomatoes in pots that are 15 to 18 inches deep. Small “patio” type varieties can be grown in smaller pots.
5. Remove lower leaves and bury part of the stem. Use seedlings big enough to have two or more leaves growing up their stem and several more at the top. Remove two or three of the lowest leaves nearly flush with the stem. Keeping the soil ball intact on existing roots, set the plant deeply enough that the places where leaves were are buried. New roots will grow there, resulting in a stronger plant.
6. Remember what you planted. After you see how your tomatoes fare, you will want to remember which bore good fruits and which were failures. So that you won’t forget which is which, use an office paper punch to make a hole in a plastic label and attach it to the plant with a twisttie. When the plant has grown taller, remove the tag and move it higher on the plant where you can see it more easily.
7. Provide support at planting time. As soon as the plant is set in the ground, set a stake or frame next to or over it. If you know that critters will want to eat your tomatoes, set the plant in a protective cage. (Consider crop cages like those on the website www.gardeners.com.)
8. Water deeply, but not too often. On the day you plant, water thoroughly — meaning water for a while so water will go deep. Set up a sprinkler or a bubbler
attachment and leave it in place to soak the soil. After that, water only when the top inch or so of soil is dry — usually every few days or weekly, depending on soil type, temperature and windiness.
9. Cover the soil around the plant with an organic mulch. Good choices are straw, leaves or compost. Keep the mulch or compost a few inches from the stem of the tomato plant.
10. Examine plants often for signs of pest damage. Inland, look into the plants to catch hornworms before these big caterpillars eat their way to the outside. Everywhere, watch for russet mites, which, though tiny, suck sap from leaves causing them to be yellowbronzy and unable to feed the plant. If you suspect russet mites, spray plants with a narrowrange oil — neem oil or any vegetable oilbased pesticide and repeat in a month. Also, tomatoes get a number of diseases best combated with resistant varieties (see above) or by removing the plant, if it is badly damaged, before it can spread a disease to other tomatoes.
Bonus tip: Be patient. If you see a tiny green fruit that has set in a flower, you are on track. However, it will take about 45 days — that’s a month and a half — for that green nub to become a fully ripe fruit.