Growing Beautiful Food: A Gardener's Guide to Cultivating Extraordinary Vegetables and Fruit (2015)

GROW

Tubers, Roots & Bulbs

ROOTS AND BULBS MAY NOT have the come-hither sexiness of their cousins aboveground, but what they lack in allure they more than make up for in longevity and flavor. Just beneath the rough skin of the earth, they incubate in mysterious mineral darkness, forming their complex carbohydrates, fiber, and phytonutrients—all essential to our health. They can even be left in the ground after frost, where their starches will sweeten, and they store so well that they’re a staple of a healthy winter diet.

Often underappreciated (maybe because they’re usually cooked into an unimaginative mush), root veggies and bulbs are wonderful eaten raw (save for potatoes), and nothing beats them in salads or as a base for nutrient-dense smoothies. They’re also remarkably beautiful: Pencil-thin baby carrots, if closely planted, will twine in a sweet, delicate embrace beneath the soil, while multicolored spring radishes, like crisp jewels of color, can be repeatedly planted for a constant supply in the cool months of spring and fall. Radishes are also one of the fastest and easiest vegetable to grow, with many varieties maturing in as little as 3 weeks. If you want to get your kids interested in food growing, easy radishes are a great place to start.

Root crops allow you to maximize the calorie and nutrient output of your farm by as much as 20 times the calories per square foot of other crops, but the trick with most roots and bulbs is the tilth, or texture of the soil: It needs to be light, rich, and well-draining. After that, they’ll work their magic for you.

Beta vulgaris

Beets never used to be my favorite. Maybe because they came in a can, floating in a purple haze of liquid, and tasted cloyingly sweet for a vegetable. That was before I learned about the smoky caramelizing that happens when roasting and grilling them or the fresh colorful ribbons of flavor they add to salads. Now I can’t get enough of them, and the beautiful varieties available to the home gardener make them even more alluring. They also make efficient use of space in the garden, giving you both the greens and the bulbs to harvest.

A sunny spot with light, loamy soil that is evenly moist and well drained is best for both tops and bottoms of sweet, juicy beets.

Plant seeds in prepared soil up to a month before the last spring frost date, spacing them 2 to 4 inches apart and covering with ½ inch of fine soil. Sow more seeds at 2-week intervals through spring to enjoy a steady harvest of roots and greens. Plant again in late summer, 1 to 2 months before the first frost date; soak seeds in water overnight before planting to improve germination.

Each beet seed in a packet is really a small fruit that may hold as many as eight actual seeds. This means thinning is important to give roots room to expand. Thin the clusters of tiny plants shortly after they come up to leave one seedling from each group. When the beets reach 2 to 3 inches tall, thin them to 4 to 6 inches apart. (Eat the tender young thinnings.) Keep the soil evenly moist to prevent flowerstalks from forming, which brings an end to leaf production and makes the roots tough and stringy. Water every 2 weeks with liquid seaweed or fish emulsion, and mulch to conserve soil moisture and keep out weeds.

Begin harvesting roots when they reach 1½ to 3 inches in diameter. Pull roots carefully by hand to minimize bruising and breaking. You can harvest up to a third of a beet’s leaves without impeding root development, but it’s sensible to make separate plantings for roots and greens to get a full harvest of each. Roots of most varieties reach maturity about 55 days after planting.

Leaf miners (fly larvae that tunnel beneath the surfaces of leaves) may target beet foliage, spoiling its looks with brown blotches or serpentine trails. Handpick affected leaves; consider covering young plants with row cover to keep leaf miners and flea beetles from ruining the greens.

Stunted roots with internal hard black spots are evidence of boron deficiency. Growing beets in compost-enriched soil and regularly applying liquid seaweed or fish emulsion during the growing season will ensure that they get enough of this nutrient.

‘Bull’s Blood’, ‘Chioggia’, ‘Cylindra’, ‘Touchstone Gold’

Daucus carota var. sativus

Carrots hide their magic for months beneath the soil, coming out of the dark in colors and shapes beyond imagining, from classic orange to yellows, creamy whites, reds, and deep purples. Harvested young, they have a delicious, earthy crunch, and when grown in winter coldframes, carrots will take on a sweetness beyond belief. They are packed, not surprisingly, with beta-carotene as well as other healthful phytonutrients.

Long, straight carrots that taper to a point need deep, loose, sandy to loamy soil that drains well but remains evenly moist and a sunny to lightly shady spot in the garden. Prepare the soil thoroughly before planting carrots, digging deeply or building a raised bed of rock-free soil amended with plenty of compost. Dig in rock phosphate and kelp meal before planting to supply phosphorus and potassium, but avoid excessive nitrogen, which can stimulate lots of slender side roots, giving carrots a hairy appearance.

Start sowing carrot seed in prepared soil 2 to 3 weeks before the last spring frost date. Sprinkle the fine seed over a premoistened seedbed and cover with ¼ to ½ inch of fine-textured soil or sand. Because carrot seeds may take up to 3 weeks to germinate, gardeners often mix quick-sprouting radish seeds in with the carrots to mark the rows. Water gently after planting to avoid washing away the seeds. Covering newly planted seedbeds with row cover can protect them from heavy rainfall and also helps prevent some pest problems. To keep a steady harvest of carrots coming, plant more seeds every 2 to 3 weeks, watching the calendar to allow the roots to reach maturity by the first fall frost date.

Keep the soil evenly moist but not soggy while waiting for the seeds to sprout. Thinning tiny carrot seedlings can be tedious, but it is essential to alleviate crowding so the remaining roots have room to grow. When the tops reach 2 inches tall, snip off or pull excess seedlings to create 1-inch spacing; thin again in 2 to 3 weeks to space remaining carrots 3 to 4 inches apart.

Be prompt about removing any weeds that crop up, and hand-pull carefully to avoid disturbing carrots’ roots. Maintain even soil moisture. Soil that dries out and then is suddenly soaked by makeup watering can cause carrot roots to split.

Begin enjoying carrots as soon as the roots are large enough to eat. Flavor improves as they grow, so the roots can remain in the ground until needed, as long as they’re shielded from hot, dry conditions and freezing temperatures. Moisten the soil to soften it before harvesting, then hand-pull mature roots. Use a spading fork or trowel to loosen the soil if necessary, taking care to avoid bruising or cutting the carrots.

Carrot rust flies and carrot weevils both lay eggs on carrot seedbeds, and their larvae tunnel into roots. Both are especially troublesome in early spring crops; rust flies may be avoided by delaying carrot planting until early summer. Rotate carrots to elude these pests and others, and cover newly sown seedbeds with row cover to block egg-laying adults.

Rotating carrots and planting in soil well-amended with compost also helps prevent problems with pest nematodes that can cause carrots to form stunted, knotty roots. Choose resistant varieties if leaf blight diseases are a known problem in your area.

‘Atlas’, ‘Atomic Red’, ‘Mokum’, ‘Nelson’, ‘Purple Haze’, ‘White Satin’

Brassica oleracea (Gongylodes Group)

Another weirdly alien-looking bulb that sits on the soil surface like a probe from another planet, kohlrabi is a must-have for both flavor and novelty. Kohlrabi is a cabbage relative that forms a bulbous “root”—actually a swollen stem—just above the soil surface. Beneath its rather lumpy green or purple skin, the flesh of kohlrabi is crisp, white, and sweet, with a mild flavor similar to a turnip’s.

Give kohlrabi a sunny spot in good garden soil that’s been amended with compost to improve drainage and moisture retention.

Plant seeds directly in the garden 4 to 6 weeks before the last spring frost date, sowing them ¼ inch deep and about an inch apart. Make successive small plantings every 2 weeks up to the last frost date rather than one large one. Kohlrabi likes cool growing conditions and its bulbs are sweetest when they grow rapidly to harvest size. Six to 8 weeks before the first fall frost date, start seeds indoors for a fall crop. Transplant seedlings to the garden when they are about 4 inches tall.

Thin seedlings to 4 to 6 inches apart when they reach 4 inches tall. Keep up with watering and apply about an inch of organic mulch around the plants to maintain soil moisture and block out weeds. Dry soil followed by a soaking rain can cause kohlrabi to split. Water with liquid seaweed or fish emulsion when plants are about 6 inches tall.

Mark the calendar to begin harvesting kohlrabi when it reaches the date indicated by the variety’s estimated “days to maturity.” Younger and smaller bulbs typically have the best flavor and texture. Start by picking 2-inch-diameter kohlrabi, cutting off the roots about 1 inch below the swollen bulb. The young leaves may be eaten like collards or kale. Monitor varieties that produce larger bulbs and harvest at the appropriate time. Kohlrabi that remains in the garden too long, particularly in hot, dry weather, tends to become tough and woody.

The same pests that riddle other cabbage family crops with holes will put the bite on kohlrabi, although it typically is less troubled than its kin. Use collars around spring transplants to protect them from cutworms; install ground-level beer traps if slugs and snails are sliming around young plants. Put row cover over young kohlrabi and seal the edges to block flea beetles and egg-laying adults of leaf-eating caterpillars.

Rotate kohlrabi and clean up plant debris after harvest to avoid disease problems common to the family. Promptly remove and destroy plants showing signs of disease.

‘Azur Star’, ‘Kolibri’, ‘Kossak’, ‘Winner’

Pastinaca sativa

Long and tender with a mild, herbal sweetness, pale-skinned parsnips are carrot’s Goth cousins and are grown much the same way. They’re delicious oven roasted with rosemary, tossed into soups and pot roasts with other root vegetables, or served as a starchy stand-in for potatoes. When harvested as baby bulbs, they can be enjoyed raw in salads; peel and shred if they’re more mature.

Give parsnips a sunny site with deep, loose, fertile soil that is moist but well drained and free of rocks and clods. Amend the bed generously with compost before planting but forgo applications of fresh manure or other nitrogen sources that can make parsnip roots grow forked and hairy.

Time parsnip planting in spring by counting back 3 to 4 months from the first frost date in fall. Parsnips may be planted in early spring as soon as the soil can be worked, but the goal is to have the roots mature around the time of the first fall frost and not in the heat of summer. Start with fresh seeds and soak them overnight before planting to encourage germination.

Sow seeds 1 inch apart and ½ inch deep in rows 12 to 18 inches apart, covering them with sand, sifted compost, or vermiculite. Parsnip seeds may take up to a month to germinate; mix in a few radish seeds to mark the rows until the parsnips appear.

Cover the seedbed with row cover to retain moisture and keep out pests. Maintain even soil moisture while seeds are germinating and seedlings are getting started. Watch for weeds and remove them while they’re small. When parsnips reach about 6 inches tall, thin them to 4 to 6 inches apart and mulch lightly. Avoid walking on the soil around parsnips to keep from damaging the long, slender roots.

Wait until after a frost or two has fallen to begin harvesting mature roots. Use a digging fork to carefully loosen the soil around the roots before pulling them up. To harvest parsnips through winter, cover the row with a 1-foot layer of straw and pull it back as needed to dig more roots. Finish harvesting by early spring, before new leaves begin to sprout. Dig the entire crop in fall if winter rains are likely to keep the soil cold and soggy for extended periods.

Carrot pests may also bother parsnips but usually to a lesser extent. Spots on leaves may indicate a fungal disease that also causes sunken red brown cankers on the tops of parsnip roots. Remove plants showing symptoms of canker disease and thoroughly clean up debris after harvest. To minimize problems, choose resistant varieties and cover exposed parsnips’ shoulders with soil.

‘Hollow Crown’, ‘Javelin’, ‘Lancer’, ‘White Spear’

Solanum tuberosum

There is so much more to potatoes than the stolid, ho-hum spuds sold in supermarkets, and few pleasures are more immediate than reaching into loose soil to pull out fresh fingerlings for the next meal or turning over abundant forkfuls of colorful tubers late in the season to stockpile for the winter months ahead.

Grown from “seed” potatoes—tubers selected from the previous season’s harvest—instead of from seed, potatoes are an easy crop to add to the garden. Growing your own vastly expands the available options in color, texture, and flavor far beyond the slim choices offered in most stores.

Potatoes grow best in light, loose, well-drained soil in a sunny spot. Dig in compost before planting to meet their modest fertility needs and to improve moisture retention and drainage. Acid soil conditions (pH 5.0 to 6.8) favor healthy growth and help prevent infection by scab disease.

Unlike their heat-loving cousins in the Solanaceae family, potatoes prefer cool growing conditions. Plant certified disease-free seed potatoes in spring, about 2 weeks before the last frost date or when the soil is at least 40°F (4°C). A day or two before planting, use a sharp knife to cut seed potatoes into pieces no smaller than 1 ounce and with two or three eyes each. Spread the cut pieces out to dry in an airy, well-ventilated place for 24 hours or more to give the cut surfaces time to harden a bit.

Plant the pieces, cut side down, 6 inches apart in a trench 4 inches deep in prepared soil. Cover with 2 to 3 inches of soil and mulch lightly.

Where the soil is heavy or poorly drained, seed potatoes may be planted on the surface of a prepared bed and covered with a deep layer of mulch. Space prepared seed potato pieces 6 inches apart in rows and cover with 4 inches of straw mulch.

As plants grow, hill up soil around the stems or add more straw mulch to keep developing tubers completely covered. Keep adding mulch until the straw is 8 to 12 inches deep; stop hilling soil or mulching when blossoms appear. In addition to keeping the soil moist and blocking weeds, mulching around potatoes prevents tubers that form close to the soil surface from turning green from exposure to light and can reduce damage caused by troublesome Colorado potato beetles.

Water regularly to keep the soil or mulch evenly moist. Foliar feed potatoes growing in mulch with liquid seaweed or fish emulsion when the plants emerge and again when they bloom to help make up for nutrients they aren’t getting from the soil.

When flowers appear, search in the soil or mulch around the bases of plants to find small “new” potatoes to harvest. Replace the mulch to shield remaining tubers from exposure to light.

Potato plants may begin to turn brown and wither as their tubers reach maturity. You can encourage this process by knocking over or cutting off the plants when they reach the number of days to maturity for the variety. If the weather is not too wet or warm, leave the tubers in the ground for a week or two to harden before harvesting.

Harvest in late afternoon or on a cloudy day. Pull plants out of loose soil or mulch and gather the tubers that come up on the roots. Then explore the hole for more potatoes. Use a spading fork to turn the soil to expose tubers deeper in the ground. Put the harvested potatoes into a bag or bucket to keep them out of the light.

Rinse or gently wipe off excess soil, then spread potatoes in a single layer in a cool, dark place to dry for 2 weeks before storing in a dark place at about 40°F (4°C). Set aside any tubers that were cut or damaged during digging and use them right away.

Wireworms are shiny, segmented brown or yellow beetle larvae that burrow into the roots of many vegetables, including carrots and potatoes. Wireworms are most prevalent in areas where grass has been growing; avoid planting potatoes and other root crops in gardens that have recently been converted from turf.

Colorado potato beetles are chunky, ½-inch-long yellowish insects with lengthwise black stripes on their backs. They emerge from the soil around the same time as early potato crops, climbing the stems to feed on leaves and lay clusters of bright orange eggs. Their voracious larvae are reddish grubs that also gobble potato foliage. Handpick these pests and crush any eggs you find. Straw mulch seems to confuse emerging beetles and may impede their progress from soil to stems and leaves.

Preventing diseases in potatoes is much easier than curing them. Rotate potatoes and related crops—tomatoes, peppers, and eggplants. Remove weedy family members like nightshade from the garden area. Buy certified disease-free seed potatoes and choose varieties that are resistant to diseases common in your area. Clean up crop debris at the end of the growing season and destroy any plants that show signs of disease.

‘French Fingerling’, ‘Gold Rush’, ‘Magic Molly’, ‘Peter Wilcox’, ‘Russian Banana’

Raphanus sativus

Radish savvy has come a long way in recent years. Once only sliced into salads or carved into florets and mildly creepy dioramas, radishes are now available in a rainbow of colors, shapes, and sizes—from gumball-like globes of pink, purple, and white to long French varieties (such as ‘D’Avignon’), pale Asian daikon, and black-skinned Spanish types. Easy to grow and quick to reach edible size, radishes can help satisfy the urge to garden in earliest spring, when conditions are far too unpredictable for all but the hardiest of crops.

Like most root crops, radishes do best in loose, evenly moist and well-drained soil that is free of rocks and clods. Dig in compost to prepare a sunny to lightly shady site for radishes, but avoid manures and other potent nitrogen sources that can promote abundant leafy growth at the expense of the roots. As temperatures rise, plant radishes in the shade cast by taller crops to keep things cool.

Start planting radish seeds in the garden as soon as the soil can be worked in early spring. Sow them ½ inch deep and 1 to 2 inches apart. Rather than planting a lot of radishes at one time, make successive, smaller plantings every 10 days throughout spring, until daytime temperatures regularly exceed 75°F (24°C). Resume planting as things begin to cool down in fall. Sow seeds of daikon and other winter radishes in midsummer for harvesting in fall and early winter.

Keep radishes evenly moist to allow them to grow quickly to harvest size—in as little as 21 days for some varieties. Thin crowded rows or beds to leave 2 inches between small spring varieties and 3 inches between larger winter radishes. Enjoy the thinnings in salads. Dry soil and high temperatures make the roots tough and fiery tasting. Mulch around summer-planted radishes to keep the soil cool and moist and to suppress competition from weeds. Radish roots may split if they receive abundant water in the wake of dry soil conditions.

Begin pulling radishes as soon as they reach mature size—in 3 to 5 weeks for most spring-sown varieties and within 7 to 8 weeks for winter radishes. Radishes do not improve the longer they remain in the soil, especially when the weather turns warm. Lingering roots lose their crisp, dense texture and become “pithy”—woody and tough—and strong tasting. Eventually, radishes left in the garden will bolt.

Radishes growing quickly and in favorable conditions rarely are bothered by problems. Cabbage maggots may tunnel into a few roots but rarely damage an entire planting. Shiny black flea beetles can be troublesome if they feed heavily on the leaves of young seedlings.

‘D’Avignon’, ‘Easter Egg’, ‘Miyashige’, ‘Nero Tondo’, ‘Red Meat’

Allium fistulosum and others

At Stonegate, we often tuck scallions between other spring greens, letting them shoot up like slender fountains between broader leaves. The purple varieties are particularly showy, and all scallions (members of the Allium family, which includes garlic, onions, leeks, ramps, chives, and shallots) will add zest and punch to the plate, whether served fresh, sautéed, or grilled.

Shallow-rooted scallions need loose, fertile soil that remains moist but not soggy in a sunny to partly shady site. Dig in compost before planting. In wet or heavy soil, plant scallions in a raised bed well amended with organic matter.

Plant seeds of scallions in early spring, as soon as the soil can be prepared, 4 to 6 weeks before the last spring frost date. Start with fresh seed and sow thickly, ½ inch deep. Mix a few radish seeds in with the onion seeds to mark the rows and to serve as a trap crop for root maggots, which prefer burrowing into radishes but will go after onions. Make successive plantings every few weeks throughout the growing season for a steady supply of scallions into fall.

You can also sow seeds of bunching onions in fall, about 4 weeks before the first fall frost date, for plants that will overwinter for harvest in spring. Mulch young scallions with 4 inches of straw in fall; remove it in early spring.

Scallions also may be grown from onion sets—small bulbs sold in spring for planting. Plant sets in early spring, 2 inches deep and about 4 inches apart. Some can be used for green onions and others left to produce mature bulbs. Onion sets usually are offered by color—white, red, or yellow—while seeds allow for a selection of superior varieties of bunching onions.

Thin young seedlings to 1 inch apart and pull out and harvest radishes once they’ve fulfilled their purpose as row markers and root maggot traps. Keep onions evenly moist to prevent splitting that can occur in dry conditions. Apply mulch after the soil has warmed up to maintain soil moisture and prevent competition from weeds. Onions are poor competitors with weeds and dislike having their roots disturbed.

Begin pulling scallions for use as soon as they reach a suitable size. Most bunching varieties mature within 55 to 65 days.

A few pests may bother onions being grown for large bulbs, but comparatively quick-growing scallions that are planted in favorable conditions and well-prepared soil usually are trouble free. Rotate onions of all types and any relatives—garlic and leeks—to avoid buildup of diseases or pests specific to the family.

‘Deep Purple Bunching’, ‘Nabechan’, ‘Parade’

NOTES FROM THE WONDERGROUND

Out of This World

With a CSA share this past week of neon purple kohlrabi, snap peas with their tender twining shoots thrown in, and a constellation of edible flowers, we’re reaching into the beyond for taste and texture. Throw in the drumming and flooding rain and the freakish 17-year cicadas whirring about, and it feels like science fiction out there.

Kohlrabi is the Sputnik of brassicas. With its gangly, outrigged antennae and swollen, spherical center, you can almost imagine it floating silently in the cosmos. And snap peas, with their clambering tendrils and pods of remarkable sweetness, are also, metaphorically at least, out of this world.

Having descended from their skyward vines on delicate white parachutes of bloom, the ‘Sugar Snap’ pods have emerged to conquer our tastebuds. And (sorry for this) they’ve come in peas.

The ongoing space race at the farm is so 1960s. Where the peas are beginning to tower, indeterminate cherry tomatoes below are competing for light and nutrients, waiting for their turn in the sky. The peas have been fixing nitrogen in the soil (something legumes do) and will make it available for hungry tomatoes.

Lettuces, too, have been carrying on well into early summer, shaded as they are by the broad leaves of kale and chard; and nasturtium, squash, and pole beans are all in a delicious tangle for limited space. At Stonegate, the universe may be expanding, but it’s not infinite.

At the moment, the war of the worlds is mostly being fought in the orchard, where the dreaded cicada mating and egg laying has begun in the fruit trees and brambles. Although I went about mercifully at first, unable to dash the hopes of so many unrequited 17-year-old virgins, I’ve had a change of heart. All it took was one look at a young quince tree, with its velveteen fruit full of promise but its outer branches collapsed and dying from the bark-piercing spawn of females cicadas, to turn me. They had me at hell, no.

So the cicada pogrom was on. Mating pairs were plucked in flagrante delicto from branch tips and crushed. Spent and feckless males were fed to excited chickens. Larvae-ridden bark has been thrown on the burn pile. It’s a winless battle, I know, but maybe it will put a dent in the next brood, or my own exasperation.

The cicadas will fly to the treetops, mate, and die. The indeterminate tomatoes and pole beans and sunflowers will defy gravity and touch the sky, the surreal climbing squash and cucumbers will curl themselves upward, and we’ll be down below, buzzed about it all. To paraphrase Oscar Wilde, “We’re all in the gutter, but some of us are looking at the stars.”