When planting veggies, it’s all in the timing

Pity the poor Europeans in the centuries before Columbus. They had none of the foods that were abundant in the tropical western hemisphere. That means no tomatoes, potatoes, eggplants, peppers, corn, beans, cucumbers, squashes or sweet melons.

If you’ll notice, these natives of the Americas are the crops we plant in April and May, now that the danger of frost is pretty much over. And that’s because of their heritage as tropical plants. Their forms may have changed over the years as breeders have selected for size and flavor, but most still can’t stand frost.

The ancestors of our tropical western hemisphere crops were also often perennials because they could survive year-round. Today, as food crops in our gardens, we treat them as annuals.

In our early spring gardening enthusiasm, we plant these tropical staples with the hope of a summerlong production of homegrown food. Tomatoes and peppers can indeed harken back to their perennial heritage by producing all summer, but you have to know a few facts to make this happen.

Tomatoes, for instance, are either determinate or indeterminate. It will say so on the packet label, in the catalogs, or on the plastic tag that’s stuck into the pot of the plant start. Determinate tomatoes will grow up, set out a big crop, and then poop out on you.

Indeterminate tomatoes keep growing all season from shoots that arise in the leaf axils, and these new shoots, called suckers, will hang out little flowers that produce fruits right up until the failing light of late fall shuts them down. To keep the plants producing, pick off the fruits as soon as they ripen.

Peppers, too, will keep producing fruits, as you keep picking off the pepper pods as soon as they ripen. The reason for this behavior is that these vegetables are going through their reproductive cycle. First come the flowers. When they are pollinated, the plant enters the fruiting stage, producing seed-bearing tomatoes or peppers. If not picked off, the plant enters the seed-ripening stage and curtails fruit production, putting its energy into ripening the seeds, which guarantees the next generation’s survival. By picking the fruits as soon as they ripen, you keep the plant in the fruiting phase.

Corn, of course, is a once-and-done crop. No use letting finished stalks take up garden space, so pull out the stalks and use them in your compost pile or put them through a wood chipper and use the chippings as mulch to suppress weeds.

The other native American crops do well in the blazing heat from May until August because of their tropical nature, but then in late July or early August they slow down and become host to mildews, fungus, and the many insects that find them irresistible (those little, greenish, black-spotted bugs aren’t called cucumber beetles for nothing).

Before Columbus, the only bean the Europeans had was the fava bean, so it was a major culinary advance when the native American bean (Phaseolus vulgaris) gave both fresh beans and dry shell beans to European cooks. Beans are a relatively short season crop, with a large major harvest occurring about 50 to 60 days after planting, depending on the variety. They do best after the soil has thoroughly warmed up. That’s mid- to late May around these parts. Planting them early does no good. If you are assiduous about picking the pods when they are pencil-slim and before the seeds inside plump and ripen, you can get your plants to produce all summer. But woe unto you if you let a plant ripen even a few pods, for then the subsequent pods will turn tough and stringy.

The best strategy is to plant your main crop of fresh snap beans in late May, harvest the crop for blanching and freezing in late July, and either replant beans for a fall crop of dry shell beans or use the space for something else.

Even if your spring crops are still producing a little food around the dog days of early August, think about pulling them out or chopping them into the soil to make room for new, fall crops that actually prefer the shorter days and cooler nights of fall. Otherwise you’ll have mostly weeds to eat from then until December.

Because your beds have worked hard since spring, it’s important to refresh them by digging well-made, rich compost into the top foot of soil, which is the zone where your fall crops’ feeder roots will proliferate. Worm castings are ideal if you can get them.

Let me suggest that you set up a worm bin at home. Harmony Farm Supply in Sebastopol carries them and can help you find a source of the red wiggler worms that will inhabit the bin. The worms will eat all your vegetable kitchen scraps except for citrus rinds, hot peppers, and anything from the onion family. They’ll turn everything else into sweet-smelling black gold that is seven times richer in nutrients than regular compost. I run three worm bins and a happier bunch of wigglers you’ll never find. They produce no odor and their castings are a miracle food in the garden and in our potted plants.

How much compost to use? Cover the bed four inches deep with compost, half that if you’re using pure worm castings, and turn it in with a spade.

Early to mid-August is the right time to plant fall crops of cabbage family members - kale, collards, cabbages, cauliflower, broccoli and kohlrabi - as well as mixed Chinese vegetables. Plant Swiss chard then, too. A crop of peas is a welcome treat in fall. Spinach planted in August will revel in the cool weather of October and November. Lettuces and other salad greens prefer cool weather. A fall crop of potatoes will yield nearly as many spuds as a spring crop. Root crops like carrots, beets, turnips and rutabagas will be ready for Thanksgiving, and for Christmas.

Jeff Cox is a Kenwood-based garden and food writer who can be reached at jeffcox@sonic.net.