Reader's Digest Quintessential Guide to Gardening

AGAVE

According to folklore, the century plant (the common name for Agave americana) flowers once every one hundred years. In fact, the plant may bloom its first and only time in ten years, then dies. Agaves grown in pots may take even longer to bloom.

A garden guardian. Plant the imposing agave around the perimeter of your property, underneath windows, or at the edges of other plantings. The needle-sharp leaves will discourage intruders and animals. But keep them away from walkways, where their sharp and spiky leaves can become a danger to friend as well as foe.

For erosion control, especially in arid regions, try planting agaves on banks. They also make excellent windscreens when planted around the borders of a large property. They’re often unsuitable for limited spaces, however, since their large size can visually dominate an entire landscape.

Climate too cold? Grow agaves, which will remain hardy down to 40°F, outside in containers in summer. When winter comes, store the plants in the basement and keep them dry.

Keep agaves neat and trim by regularly removing the untidy lower leaves. And remember that agaves die after they flower. Remove the entire plant once blooming is completed and the rosettes have died.

ALKALINE SOIL

Add a few drops of cider vinegar to a soil sample. If it fizzes, the soil is alkaline. For a precise reading, contact your local Cooperative Extension Service to learn how to take a sample and where to send it. Or pick up a home test kit online or at a local garden-supply store.

Reduce alkalinity by adding acidic materials such as peat moss, sulfur, or aluminum sulfate to your soil. To lower the pH by one unit, add 5 pounds of peat moss, 1/2 to 2 1/2 pounds of sulfur, or 5 to 15 pounds of aluminum sulfate per 100 square feet. Use the smaller amounts of additives in sandy soils and progressively larger amounts in heavier soils. Improving drainage may help reduce alkalinity by allowing water to wash through and carry away alkaline salts. Put plenty of dead leaves, compost, or other organic matter into the bottom of planting holes. Coffee grounds help reduce alkalinity, too. Dig a good helping into the soil. Blanketing the ground with an organic mulch prevents surface evaporation of water and the buildup of alkaline salts.

In western states, alkaline soils tend to be high in sodium, which makes them tight and sticky. Water the soil to loosen it. After it dries, dig in gypsum—about 2 pounds per 100 square feet of moderately clayey soil.

Make the best of it. Instead of acidifying your soil, consider growing plants that like it alkaline. Desirable flowers in this category include the Madonna lily, purple coneflower, phlox, and candytuft.

ALOE

Warmth and sunlight are keys to growing these African natives, so place aloes in full sun—except those with speckled leaves, which need midday shade. Rich soil, good drainage, and regular summer watering are also important. Most species won’t survive temperatures below 40°F, so frost protection is often needed in cooler climes.

Add year-round drama to your garden by planting aloes in large groupings. Many species—including Aloe ferox and Aloe brevifolia—flower during fall and winter when little else does, and mass plantings tend to emphasize the bright display of gold, coral, and orange flowers. Choose small to medium varieties and install them in rows, with each plant 18 to 24 inches apart. The plantings will expand into attractive large clumps within two to three years.

Leave the earth bare around aloes to highlight their striking sculptural quality. And regularly groom older clumps to keep offshoots from cluttering up the plant’s inherent neatness and simplicity.

To grow aloes in pots, provide a moist, porous potting mixture by using 2 parts soil, 2 parts perlite or coarse sand, 1/4 part bonemeal, and 1/2 part dehydrated cow manure. Keep your potted aloe at a minimum of 50° to 55°F.

ALUMINUM FOIL

Protect young trees from mice and rabbits. Wrap trunks loosely in sheets of foil to a height of 18 inches. The glittering, rattling surface keeps the gnawers away.

Use aluminum foil mulch to speed growth and protect against insects. Stretch it between rows of plants and use rocks or bricks along the edge to anchor. The light the foil reflects can increase yields, especially in cloudy regions, and speed the ripening of tomatoes or the blooming of a rosebush by a full two weeks. The foil also keeps thrips and aphids away.

A cheap substitute. If you’re using large amounts of foil, save money by painting black plastic mulch with the aluminum-colored paint sold at hardware stores.

Foil scarecrows. Keep birds away by cutting patterns from cardboard—stars, circles, seashells—and wrapping them in foil. Hang from the branches of ripening berry bushes and fruit trees.

Cones for bulbs. Give forced crocus and hyacinth bulbs the darkness they need by placing them on a chilly windowsill and covering with a cone of foil. Remove the foil when crocus shoots reach 2 inches and when hyacinth shoots reach 4 inches.

ANNUALS

Purchasing

Young plants in six- or eight-packs of the same variety are often available at very low prices. The seedlings should be well rooted but need not be in bloom. Once planting season is past, however, beware of starved, dried-up leftovers.

Climbing annuals will quickly disguise a chain-link fence or the screening around garbage cans. Morning glory, scarlet runner beans, black-eyed Susan vine, sweet peas, and hyacinth bean are some of the climbers that do the job nicely.

A few for shady gardens: Impatiens, monkey flower, nasturtium, California bluebell, and wishbone flower are shade-tolerant annuals.

For pots and window boxes, choose bushy or trailing annuals. Petunias, marigolds, verbenas, thunbergia, lobelia, and heliotrope are ideal. But avoid tall plants like sunflowers, which look awkward in small containers.

Planting

The right place. A sunny location with good drainage is more important to most annuals than soil quality.

Use as fillers. Plant annuals in the empty spaces between shrubs, foundation plants, perennials, or rows of vegetables.

Sow half-hardy annuals indoors to give them a head start. To make sure they’re evenly spaced, place chicken wire over your seeding tray and put a seed in each hole. This makes it easier to separate the seedlings for transplanting.

Flowers all season. While you wait for perennials to take hold, dress up the garden with annuals. Since they germinate, bloom, and die within a single season, there’s no need to dig them up once the later flowers are established.

Color considerations. Massing a single color will create an elegant, unified effect suitable for terraces, planters, and window boxes. Pastels—white, pinks, lavenders, yellows—show up best in early morning and evening light. If you want a multicolored effect, make a sketch and color it in; it will help you keep the colors harmonious.

Maintenance

Good and wet. Plenty of moisture is essential when you set out young plants. First, soak them in a tub of water. Plant only after the root ball is thoroughly wet. As extra insurance, soak the planting hole with a good watering as well.

Annuals don’t like manure—even when it’s well aged. Too much nitrogen results in plants with too many leaves, too many stems, and too few flowers. The only manure suitable for use on annuals is one that has dried for at least two years.

Pinching young plants delays blooming but helps them become stockier and bushier. Annuals such as clarkia, sweet pea, cosmos, godetia, coleus, snapdragon, nicotiana, red salvia, and petunia benefit from pinching. Use your thumb and forefinger to nip out the growing tip of the main stem just above a leaf or pair of leaves.

Which to deadhead. Use shears or scissors to remove dead flowers from annuals that bloom in flushes, like coreopsis, petunias, California poppies, and marigolds.

Put annuals into pots at the end of summer. Species such as coleus, impatiens, browallia, geranium, floss flower, and wishbone flower will provide attractive blooms in your home for several months.

ANTS

Gardeners usually consider ants to be pests. Ants can loosen the soil around young plants, causing them to die. Some species shelter and protect aphids, whose honeydew they feed on. On the positive side, ants can improve air circulation in heavy soils, and their burrows improve water drainage.

To get rid of a colony, cover the anthill with a large flowerpot whose drainage hole has been plugged with a cork or tightly wadded plastic wrap. Heat a bucket of water to boiling and flood the surrounding soil, reserving a few gallons of the water. Wait a minute or two for most of the ants to find shelter in the overturned pot, then turn it upright and pour in the remaining water. Boric acid mixed with sugar is an effective ant poison—but only in gardens with no children and pets. Spread it on a piece of wood or stone near the nest, then cover for protection from rain. The foraging ants will love it.

A mash of hot chilies and water will keep ants away. Another homemade repellent is a mix of orange peels and water puréed in your blender and poured directly into an anthill early in the morning.

Ants hate aromatic plants like mint, lavender, chives, and garlic. Install these along borders or spot them randomly in clumps and pots around the garden. Create an ant barrier around plants, on front steps, and between garden rows with a sprinkling of agricultural lime, bonemeal, or powdered charcoal.

Fire ants, better known in the South as red ants, are especially partial to sun and sandy soil. If your yard is prone to infestation, provide shade with vine-covered trellises in a part of the garden where sun-loving plants won’t be affected. And if you keep compost, store it in closed bins so that fire ants can’t use it to build their hills.

APHIDS

Get rid of aphids the first time you see them; these pests reproduce rapidly. They not only suck the nutrients from a plant, but can also spread any number of deadly viruses, including bean mosaic virus and cucumber mosaic virus.

A simple and effective spray for aphids is 4 ounces of dishwashing liquid in 1 gallon of water. For another good spray, mix 1 tablespoon liquid soap and 1 cup vegetable oil, then add 2 teaspoons of the blend to a gallon of water—but don’t use it on squash, cauliflower, or cabbage, which can suffer leaf burn. When using either recipe, spray the plants with the mixture and follow with a spray of water. Wait about fifteen minutes and repeat.

Sprinkle wood ashes over bushes and low-lying plants; they are caustic and will dehydrate and suffocate aphids. Use a large-hole shaker—the kind for grated cheese works well—or sprinkle them on by hand. After a day, wash away the ashes with a hose.

Praying mantises, ladybugs, and aphid lions (the larvae of green lacewings) are natural foes of the aphid. Obtain them from garden-supply stores and catalogs. Release ladybugs at night so that they won’t fly away. Hoverflies and wasps kill aphids by injecting their eggs into them. Plant Queen Anne’s lace to attract wasps and marigolds to attract hoverflies.

ARBORS

Tucked away in a secluded nook and sheltered by fragrant flowering vines, an arbor becomes a romantic hideaway. Set off by itself, it can accent the garden, offer an inviting destination, or command an imposing view. Arbors have utilitarian value as well. They provide shade in summer and serve as year-round screens for garden work areas, too. Traditional arbor plants include clematis, jasmine, wisteria, climbing roses, ivy, and, of course, grapes—a favorite since the time of ancient Rome.

A pergola is an arbor that you walk through. It can be a simple open framework or a series of arches that create a tunnel effect. Pergolas should have a focus—a destination, a view, or a path along a garden or across a lawn.

Design in proportion to the plantings your arbor will support. Anticipate the size of fully grown vines and climbers. Delicate latticework cannot support mature wisteria, while heavy timbers will dwarf a fragile clematis. The best woods for arbors and pergolas are redwood, cedar, cypress, teak, oak, and locust. Use only heartwood, since sapwood will decompose rapidly. Pressure-treated lumber is an inexpensive alternative that is useful when lumber must be in contact with soil. It tends to bow and split, however, and doesn’t take stain well. Pave the area beneath your arbor with brick, flagstone, or gravel if the arbor casts dense shade. Grass cannot survive without sunlight.

ARTICHOKES

Artichokes usually take more than 150 days to mature from seed and are highly sensitive to extremes of hot and cold. Coastal areas where temperatures don’t fall much below 10°F and rarely go above 75°F are the best places to grow them. In areas with cool summers and deadly winters, however, you can grow artichokes as annuals—and take your chances.

To grow artichokes as annuals, soak the seeds for two days at the end of January, then mix with moist sphagnum moss. Refrigerate for four weeks in an unsealed plastic bag. When roots emerge, pot the clumps in 6-inch plastic pots of sterilized potting soil and place in a cool but sunny window. Two weeks or so before the predicted date of the last frost, harden off the seedlings by setting them outdoors in a cool but frost-free spot during the day. Plant in well-dug soil, spacing 3 feet apart, when all danger of frost has passed.

For tender artichokes, speed the growth of the buds by keeping the plants well watered. Mulch with compost or peat moss, and work some well-rotted manure into the soil.

If you grow them as perennials, get ready for winter by cutting off the large outer leaves and tying the center leaves together. Wrap in butcher paper and pile up sand, sawdust, or dead leaves as a protective screen against frost.

ASHES

Ward off slugs and snails by encircling your plants with a ring of ashes about 6 inches out from the stem. The soft-bodied creatures will turn the other way.

Your fireplace is a built-in source of garden fertilizer. Use the potash-rich ashes for most vegetables and flowers—except for acid lovers like azaleas and heathers. Store wood ashes in plastic garbage cans or heavy trash bags. Many of their nutrients—including potassium, phosphorus, and calcium—degrade rapidly when the ashes are moist. Fertilize with ashes a week or so before you plant. Spread 5 to 10 pounds of ash per 100 square feet over freshly cultivated soil or in furrows. Hoe in lightly. Don’t mix ashes with manure or other nitrogenous materials, except for those already in the soil.

Make soil less acid by simply digging in wood ashes, which are strongly alkaline.

Heap a mound of wood ashes around the stumps of fragile plants like rhubarb, hardy fuchsias, and ferns to protect them in the winter. Rain effectively leaches nutrients from ash and supplies it to the root systems of the plants.

ASPARAGUS

Put in about twenty-five asparagus roots for each member of your family—more if youll be canning. Allow 25 feet of row for every twelve plants, with the rows spaced 4 to 5 feet apart. If you can’t plant immediately, keep the roots covered with damp sand or cloth.

If you’re not sure the roots you’ve bought have been disinfected, soak them for fifteen minutes in a solution of 1 part household bleach to 3 parts water. Give them a good wash before planting to prevent the disease known as crown gall.

Plant each root about 8 inches deep—just enough for the crowns to be covered with an inch or two of soil. Place them 18 inches apart in the rows. Properly planted and maintained, an asparagus bed will yield a harvest for twenty years or longer. Just make sure the soil is rich in organic matter.

Mulch your asparagus bed every fall and spring to maintain a continuous 4- to 6-inch cover. Don’t use sawdust or bark, both of which are too acidic. Asparagus likes a soil near neutral, or pH 6.5. Your autumn addition should include a 2- to 3-inch layer of manure as well.

Despite what you’ve heard, you don’t have to wait until the second or third year to pick asparagus. The initial harvest should be limited to two to three weeks; add an extra week