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These 'warm-weather crops' can handle the heat

Lately I've heard people say, "Oh, I missed the chance to get in a vegetable garden this year." But that's only half true. Here's the confusion: It is late to plant one group of crops but perfect for planting another group.

"Cool-weather" or "cool-season crops" -- peas, lettuce, spinach and cole crops (broccoli, cabbage, cauliflower) -- just don't do well in summer heat. They become tough or bitter or "bolt," meaning they rush to form seeds. You can always plant them much later this summer for a fall crop.

But "warm-season crops" thrive from a June planting. They require warm soil and warm daytime and nighttime temperatures to grow well, and they have many problems if we plant them too early.

Since our growing season is short, read plant labels to choose some with the least "days to harvest." It's worthwhile growing these summer-loving plants.


Studies have shown that June-planted tomatoes often catch up to the ones your neighbor planted in May. They require soil that stays over 55 degrees and nights that don't dip below 55 degrees. So move boldly forward to the plant shop and choose some tomato plants, preferably several varieties, including some early ones. Don't necessarily take the plants with little tomatoes already on them (or pick them off), as tempting as they are. The plant needs to get some roots going, and then it will be ready to produce a large crop.

Plant with a lot of compost or manure, and water well all month -- any time the top 2 inches of soil feels dry. I grow organically and like to fertilize with fish emulsion fertilizer monthly. Since tomatoes like heat, a black plastic mulch is a good way to increase the temperature while blocking the weeds.

It's important to space tomatoes far enough apart (see labels), since they get much bigger than you tend to believe when you look at the little seedlings. When you crowd them you increase the likelihood of some fungus diseases, and you can't get at them at picking time.

To stake or not? Tomato growers don't all agree. If we know we'll continue to have a wet season, staking or caging makes healthier tomatoes. (Rots and other diseases thrive among the moist vines draped over the soil.)

But if we have droughts, the vines on the ground hold in some moisture. Personally, I have always caged them with homemade circles of hog wire or tomato wire stapled to 6-foot stakes. (Yes, most tomatoes, including cherry tomatoes, need that size cage. Many commercial cages are often too small and eventually just tip over.)

If you have shied away from growing tomatoes because you fear the terrible tomato blight we saw last summer -- don't. It does not remain in the soil, only in actual tomato plants (those free "volunteers" that come up, or withered plant parts that stuck around on cages or in the compost pile.) So grow them with confidence -- or get thee to the farmers' market.


Do grow beans, if you have any open soil. It's such a pleasure and a great crop for sharing with children. They can poke the little beans just under the soil at planting time, and they can learn to be bean-pickers later on.

You can grow pole beans up stakes that are tied together to form a teepee, or you can grow them right up the corn stalks on the edge of a patch. They can also grow on any trellis or lattice, and they can work as a shade barrier to keep salad greens cool a little while longer.

Bush beans are equally versatile and are great in a combination planting with potatoes. It's not too late now to group a couple more crops of beans, planted two weeks apart.

When beans (or peas) finish, turn the whole plant into the soil; they are nitrogen-fixing and make the soil better than they found it. You can even purchase beans that will be purple, yellow and green. So what's not to like?

>Vine crops

I used to think it was silly to see cucumber, squash and pumpkin plants in garden centers and farmers' markets, because it's so easy to grow them from seed. But now I understand how busy people get a late start, so it makes sense to buy the plants.

Vine crops do need space, so read and heed those packets or labels. Some can climb on trellises -- mainly cucumbers and gourds. All love heat, and I have used large sheets of heat-reflecting black plastic with holes in it for the plants. Leave 15-inch holes at least, with the plastic around the plants tucked down so water flows toward the hole.

Some problems arise with vine crops, and you might as well expect them. Most get powdery mildew eventually. You can use horticultural oils and other gentle fungicides, and often you can just pick off the worst leaves, live with it and still get the crop.

Real troubles come from the squash vine borer and a couple of other insects, and it's worthwhile to prevent them with "floating row covers" or tunnels, made from synthetic fabrics. One well-known brand name is Reemay. Simply cover the crop with the white sheets at planting time and leave them on until you have blossoms. The pests never get to lay their eggs.

A word about squash types: It's no joke; there's always too much zucchini. And there's nearly never enough winter squash, especially with all the amazing, colorful, weird-looking varieties available.

>Combinations and companions

It's good to combine flowers and herbs with all the vegetables, to attract the beneficial insects that help control pests. You can learn how to do that, and all the details on growing cool and warm-season crops in my own book, "Great Garden Companions" (Rodale Books).

The simple version is: Just plant a few more vegetables (with some flowers) this week, and be amazed at the satisfaction and pleasure you get back from the plants and the process.

Sally Cunningham is a garden writer, lecturer and consultant.

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