Summer’s Healthy Harvest

he wide variety of produce available from my gardens in the summer is a delight. But each year, I anxiously await the chance to bite into the first homegrown tomato of the season. Although I mostly grow hybrid tomatoes in Arizona, as they’re best suited to the extreme desert climate, I prefer the flavor of heirloom varieties, which thrive in my garden in British Columbia. In particular, I’m a big fan of Brandywine, a large red-pink variety that dates back to 1885. Although these tomatoes don’t look beautiful by supermarket standards—they can be quite odd-shaped—they taste superb.

Read on for what makes tomatoes and other classic summer crops so nutritious, plus tips to get them growing in your own garden.

Cucumbers

Cucumbers, Cucumis sativus, fare well in containers, since containers heat up and dry out quickly. Cucumber roots prefer warm, dry ground—they don’t like “wet feet,” gardener lingo for soggy soil. They do well in raised beds for the same reason. If you want to sow them directly in the ground, you can plant them in a small mound of soil about four or five inches high (as is done in Three Sisters gardening; refer back to pages 48-49). The mound will help with drainage.

Choose a spot near a wall or plan to trellis your cucumber vines. Sow four or five evenly spaced seeds in the mound, leaving a couple of inches between seeds. Though cucumber roots will rot in saturated soils, because of their large leaf surface area and their preference for full sun, it is important to keep them moist enough to prevent the plants from withering. A rich soil will promote healthy green growth, and a single feeding of potassium when blossoms first appear will ensure fruit production. Try blending a small amount of organic vegetable fertilizer into the mounds at seed-sowing time.

When the plants have six to eight leaves, the growing tip may be pinched out to encourage a bushier shape and enhanced female flowering. Greenhouse cucumbers, which require special care, are hybrids that produce only female flowers.

Slugs and snails will destroy young cucumber seedlings, so if you live in an area prone to them, be proactive to prevent their damage. Handpicking by flashlight at dusk is the best method. Peek under pots and low leaves. My friend and expert gardener Jace Mortenson also taught me this trick: Sink a pie dish to ground level and fill it with beer; it will attract and ultimately drown them.

Striped cucumber beetles, Acalymma vittata, are perhaps the cucumber grower’s worst enemy. You can easily identify them by their yellow to orange and black stripes. Adults emerge in spring to eat leaves and pollen. When cucurbits (squash and melon plants) begin to sprout, adult beetles lay their larvae around the base of the plant. Larvae feed on the roots. Then, when the cucumbers flower, the beetles devour the tiny yellow flowers of the cucumber. They also transmit bacterial wilt and mosaic virus from infected plants. Try a light insect barrier like a garden netting or fabric over your cucumbers, or use organic pesticide products containing pyrethrum or neem (see page 50). Handpicking is also advisable.

Cucumber mosaic virus can attack individual plants. You’ll know your plants have it if the leaves develop yellow spots and blotches and become distorted. Remove these plants from your garden immediately.

During the peak of the season, you could be harvesting ripe cucumbers every day or two. Ripe cucumbers have a firm, green flesh—they don’t continue to ripen once picked, so you’ll want to harvest them when they’re ready. Cucumbers left on the vine too long can become bitter.

Cucumbers are very low in calories and provide some vitamin C, beta-carotene, and manganese plus a number of flavonoid antioxidants, including quercetin, apigenin, luteolin, and kaempferol.

I hope your garden produces a bounty. That way, you can enjoy them in salads and on sandwiches and still have plenty left over to make your own natural pickles (learn more about preserving on page 116).

Tomatoes

As I shared earlier, it’s difficult for me to grow heirloom tomatoes in the Arizona climate, which is unfortunate. Heirloom varieties tend to have better flavor and better nutrient content than their hybrid counterparts.

Experts define heirlooms in varying ways. Generally speaking, they are varieties that are at least 50 years old. All heirlooms fruits and vegetables are open-pollinated, meaning they’re pollinated by nature (the wind and insects) and breed true from seed.

While you can usually recognize them by their appearance—their varied colors and odd shapes mean they don’t look like the typical tomato on the store shelf— you can also often tell them by their unique names. Some standouts: Mortgage Lifter, Bloody Butcher, and Oxheart. As hybrid tomatoes made their way into gardens, offering consistent shape and color, disease resistance, and big yields, heirlooms became less popular. But I’m excited to see a resurgence of interest in growing and eating these tomatoes. You can even find them in select groceries today. Importantly, there is some evidence that heirloom tomatoes offer greater nutrient density than hybrids, especially when it comes to lycopene and vitamin A.

This isn’t to discount hybrid varieties. Hybrids are bred for disease resistance, heat/cold tolerance, shelf life, or appearance. Some are excellent and certainly worth trying in the home garden.

Whether heirloom or hybrid, tomato varieties will always be listed as determinate or indeterminate. Determinate varieties have a sturdier, more upright structure and produce one big crop and not much else. Indeterminate varieties are more vine-like plants that produce a first crop and then continue to bear fruit. I think these are often better for the home gardener, as they offer a longer season for fresh-picked fruit.

Tomato seeds should be started a couple of months before the last frost. The soil needs to be warm for the seed to germinate, so you can start them on a bright windowsill, a radiator that doesn’t get too hot, or on top of the refrigerator. A yogurt cup, some potting soil, and a little water are all you need to start, and, of course, the seeds. You can expect the plants to get tall—check the seed packet to find out how high—so they’ll need to be staked. (There are hybrid varieties selected for their compact nature and even container-sized plants.)

Ripe tomatoes are abundant in vitamin C, biotin, vitamin K, and carotenes. The carotene known as lycopene—which gives tomatoes and other red fruits their bold hue—is a powerful antioxidant that can “quench” free radicals that damage cells. Excessive free radical damage has been implicated in the development of heart disease and many cancers, as well as accelerated aging. Indeed, preliminary research shows that lycopene may help prevent cardiovascular issues as well as breast and protest cancers. It may also be the most powerful carotenoid against singlet oxygen, a highly reactive form of oxygen that is a primary cause of premature skin aging. Lycopene’s bioavailability increases with cooking, so be sure to enjoy your homegrown tomatoes both raw and cooked.

Zucchini

A type of summer squash, zucchini is the perfect plant for the beginning gardener, or for anyone looking for a vegetable with dramatic growth and high yields. One or two plants will provide you and your neighbors with enough squash for the season. The trailing vines are fascinating to watch grow, and they boast bright yellow flowers, which are themselves edible. Other popular summer squash varieties include crookneck and pattypan. Crooknecks are plumper than zucchini with a curved neck. Pattypans look like flying saucers.

Summer squash were once commonly grown on compost heaps. The rich, moist, decaying matter provided ample nutrients to produce the vine and its fruit. Conveniently, at the end of the season the old, tired vines could be turned under to replenish the pile. If you’re going to plant them in your garden, you’ll need a sunny, open location with ample space. As with all varieties of squash, a rich, organic soil is necessary to produce long, lush vines and large fruit. Well-watered and well-fed squash do best, though I have found that when it comes to summer squash, as long as the soil is rich and moist, minimum care is sufficient.

As with cucumbers, slugs can be a problem for squash. Try the pie pan in beer method (page 53) or resort to handpicking for tried-and-true control.

Zucchinis can be harvested and eaten within two to seven days after flowering. Don’t allow them to grow more than roughly 10 inches long on the vine; although they remain edible, larger zucchini become tough, dry, and relatively tasteless. Young, tender summer squash taste best.

While they may not be as nutritionally impressive as other vegetables—they do offer up carotenes, potassium, and vitamin C—the summer garden just doesn’t seem complete without summer squash growing steadfastly in the corner.

THE PERFECT PICKLER?

The best pickles are made with “pickling cucumbers,” special varieties that are firmer and smaller than “slicers.” Whatever you’re growing, if you plan to pickle, harvest your cucumbers before they’ve reached maturity, at the size of your preference—usually between two and six inches. As fermented foods, natural pickles are good sources of probiotics, which help the digestive system function optimally and may even boost immunity.