Читать книгу Home Gardener's Annuals - Miranda Smith - Страница 10

Growing your own seedlings affords you a greater choice of plants and cultivars for your garden than purchasing plants from the local garden center. And seeds are much cheaper than plants sold by mail-order nurseries. You can sow seeds for hardy plants directly in the garden. But tender plants and slow-growing ones are often started indoors to produce plants that flower earlier than they would if sown outdoors.

Before you plant any seeds, be sure the containers and tools you plan to use are clean because seedlings are easy prey for disease-causing organisms. If you are reusing starting containers, scrub them out with a 10 percent bleach solution, and let them dry before filling them with soil.

Many people start seeds in a sterile soil mix or growing medium. A number of commercial seedstarting mixes are available, but you can make one from equal parts of peat moss, vermiculite, and perlite. Add two parts of fully finished, good compost to this basic mixture if you want the potting soil to supply nutrients for the first few weeks. Although compost is not sterile, it usually contains enough beneficial microorganisms to combat injurious ones.

PLANTING SEEDS

Most seed packets carry instructions for planting depth and spacing. A general rule of thumb is to plant seeds at a depth that is two to three times their diameter. Tiny seeds (those of begonias or snapdragons, for example) can be mixed with sand to help separate them and make them easier to handle; sprinkle this mixture on top of the potting mix. Most tiny seeds need light to germinate, so it’s important not to cover them after planting. When you mist the soil surface to water them, they’ll work themselves into tiny niches that will keep them moist. Plant larger seeds in individual holes, or make furrows as you do in the outdoor garden.

Some gardeners cover their seeds with a thin layer of fine sphagnum moss to protect the seedlings from damping-off (a lethal fungal disease). Sphagnum moss has fungicidal properties. If you use it in your seed flats, make sure it stays moist at all times. When the moss dries out it becomes hard and stiff, and tender seedlings may have difficulty penetrating it. Although it was used to dress wounds during World War II because of its fungicidal properties, some people experience skin irritations if it gets into cuts or scratches; wear gloves when you work with it.

Temperature. The best temperature for germination varies from plant to plant. Generally speaking, tender (frost-sensitive) plants usually sprout best in warm temperatures of 70° to 75°F. Cool-season flowers germinate better in cooler temperatures around 60° to 65°F. Some plants need a period of freezing or cooling at temperatures of 35° to 40°F before they can germinate. Seed packets often supply this information.

Sow seeds that are large enough to easily handle one or two at a time into flats, cell packs, peat pots, or other containers of moist potting mix.

Carefully cover seeds that don’t need light to germinate by sprinkling fine, loose, moist potting mix over them to the correct depth.

Light. Seedlings need plenty of light as soon as they break through the soil surface. Fluorescent fixtures are the best way to supply light for indoor seedlings. Their light is very even, and the plants don’t need to be turned to grow straight. You can use special “grow light” tubes, full-spectrum daylight lamps, or a combination of warm white and cool white tubes. Set the lights on a timer so they’re on for 16 hours a day. The tops of the seedlings should be no more than 3 or 4 inches below the lights for the first couple of weeks; later you can gradually raise the lights to 5 inches above the leaves. Start out with the seedling flats elevated on some sort of stand that can be gradually lowered as the plants grow taller. (A pile of books works nicely.) Or suspend the light fixture on chains that you can raise or lower as the plants grow.

If you want to try growing seedlings without using artificial lighting, your best bet is a south-facing window covered with sheer curtains (to keep the heat from becoming too intense) or a bright, unshaded east or west window. Turn the flats every day to keep the stems growing straight.

Water. Seeds and young seedlings need to be watered carefully so that the seeds aren’t washed out of the soil and the delicate new roots aren’t disturbed. The best approach is to water from below, setting the flats or pots in lukewarm water in a sink or special watering tray. Watering from below allows you to evenly and thoroughly moisten the soil without dislodging seeds or tiny seedlings, as can happen with a stream of water from overhead. Set flats or pots in a container of water an inch or so deep until the soil surface feels moist, or use a specially made flat and wicking mat. This method gives you the most control over the amount of water your plants receive. Another technique is to mist the soil surface with a plant mister until the soil is thoroughly moistened. If you use this method, be sure to keep an eye on the soil. Make sure your seedlings don’t dry out; water stress can set back young plants permanently, so you will need to be attentive until the plants are well established. But don’t overwater either. Constantly soggy soil encourages root rot and damping-off. Water your seedlings when the soil is somewhat dry—early enough so that leaves can dry by dark.

Fluorescent lights provide a very even light to plants. For best results, use a timer to keep the light on the plants for 16 hours each day.

Feeding seedlings

Because the soilless mixes for seed-starting contain almost no nutrients, you’ll have to supply some as soon as seedlings develop their first true leaves (the second set they form). But don’t go overboard; overfertilizing seedlings can result in weak, floppy plants more prone to problems. Young seedlings can’t handle full-strength fertilizer. Dilute liquid fertilizers to one-quarter the recommended strength (or if you use fish emulsion, half strength). Use the diluted fertilizer once a week for the first three or four weeks. After that, gradually work up to using a normal dilution.

If you’ve added compost to the seed-starting mix, you can probably wait to feed your seedlings until they are four or five weeks old. But check their color every day; at the first sign or yellowing or purpling, begin feeding once a week with a half-strength dilution of liquid fertilizer.

TRANSPLANTING PLANTS IN PEAT POTS

Seedlings in peat pots need special treatment at transplanting time; peat pots can be so rigid that roots have difficulty breaking through them. Set the pots in a water-filled tray for 30 minutes to an hour before transplanting. When you plant, tear through the sides of each pot, and place the seedling so that the pot rim is below the soil surface, left. You may need to tear off the top ½ inch or so; if the rim sticks out of the soil, it can dry and act as a wick, drawing moisture out of the soil and evaporating it into the air. On a sunny, breezy day this wicking action can cause serious water stress for young plants.

Harden off seedlings in a cold frame by opening the lid for a gradually increasing length of time over several days, finally leaving it open all night, middle.

Thin seedlings by snipping them off with sharp scissors instead of pulling them up to avoid disturbing nearby roots, right.

THINNING AND TRANSPLANTING SEEDLINGS

When the seedlings develop their first true leaves—the second set of leaves to grow but the first that have the plant’s characteristic shape—it’s time to thin. You can thin by pulling up unwanted seedlings individually, snipping off the stems at soil level with nail scissors, or carefully lifting and transplanting the young plants to other containers.

Spacing for seedlings in flats or pots depends on the size of their leaves, but 3 inches is considered a good average spacing distance. Crowding seedlings together increases root competition, encourages the spread of damping-off and other diseases, and causes plants to shade each other, which makes them spindly. To avoid problems, keep seedlings far enough apart so their leaves don’t touch. When the leaves threaten to touch each other, the plants are probably big enough to go into individual pots or, if weather conditions are appropriate, outdoors into the garden. (See “Transplanting Outdoors,” right.)

If you’ve grown seedlings in an unsegmented flat, cut the soil into blocks a few days before transplanting. The cut roots will heal before the plants are transplanted.

HARDENING OFF

Seedlings started indoors need to adjust gradually to the harsher environment outdoors. Leaves, like skin that’s been indoors all winter, can easily get sunburned. Before you move your indoor seedlings out to the garden, harden them off. Over a two-week period, cut back on watering slightly while also increasing their exposure to colder temperatures. Begin by setting seedlings outdoors in a sheltered spot for an hour or two; then bring them back inside. Move them outside for a longer time each day, eventually leaving them out overnight. By the end of the second week the plants should be ready to move into the garden.

Another method that works well is to place the plants in a cold frame. Plants can be hardened off in a cold frame if you open the lid a bit farther each day, removing it entirely for the last two or three days.

TRANSPLANTING OUTDOORS

Transplanting to the garden is largely governed by weather conditions. The best time to transplant is on a cloudy, calm day, ideally in mid to late afternoon. Bright sun and wind can dry out transplants.

Dig the planting hole before you remove a plant from its pot or flat, even on a cloudy, humid day. This advance preparation should protect the roots from drying out. Planting holes must be big enough to comfortably accommodate all the roots and deep enough to allow the plant to sit at the same depth as it did in its growing container. If the garden soil is dry, pour some water into the hole before planting. Set the plant in the hole, and fill in around its roots with soil. Firm the soil gently; don’t compact it. Then water the plant.

Protect your transplants from wind and bright light for the first few days. Floating row covers, made from lightweight spun polyester fabric, are convenient to use and effective for shading. Glass or plastic cloches, plastic gallon jugs with their bottoms cut out, and floating row covers all give wind protection.

SELF-SOWERS

Some annuals plant themselves. If you don’t deadhead, or remove the faded flowers, their seeds drop on the ground and produce a new generation of plants the next year. If you like serendipity, let a few plants go to seed and allow the volunteer seedlings to grow where they will. If you want more control, transplant the volunteers in spring. And if you don’t want to have volunteers, deadhead before plants have a chance to form seeds.

Many self-sown seedlings don’t produce plants identical to the parents. The flowers are often smaller and the colors different. Petunias, for example, tend to revert to the magenta-purple color of the original species form of the plant. Such variation can wreak havoc with a carefully planned color scheme, but it can be fun to see what you get from one year to the next.

The following annuals are likely to self-sow in your garden:

• Bachelor’s button (Centaurea cyanus)

• Candytuft, annual (Iberis umbellata)

• Cosmos (Cosmos bipinnatus, C. sulphureus)

• French marigold (Tagetes patula)

• Impatiens, bedding (Impatiens walleriana)

• Nasturtium (Tropaeolum species)

• Petunia (Petunia x hybrida)

• Poppy, annual (Papaver species)

• Pot marigold (Calendula officinalis)

• Rocket larkspur (Consolida ambigua)

• Rose moss (Portulaca grandiflora)

• Sapphire flower (Browallia speciosa)

• Snapdragon (Antirrhinum majus)

• Spider flower (Cleome hassleriana)

• Sweet alyssum (Lobularia maritima)

• Johnny-jump-up (Viola tricolor)

Marigold Volunteers

Calendula Volunteers

PLANTING SEEDLINGS

Most gardeners buy at least some annuals from local garden centers and nurseries. They’re usually sold in plastic cell packs (sometimes called “six-packs”). It’s important to know how to handle seedlings when you bring them home and how to transplant them from cell packs—whether into the garden or a container.

Resist the temptation to buy seedlings already in bloom, as are these celosias. Even though blooming plants provide an “instant” garden, younger seedlings not only transplant more easily but they are also healthier in the long run. Whenever possible, purchase seedlings that are still “green,” or not yet in full bud or bloom.

PLANTING FROM A CELL PACK

When planting annuals in beds and borders, mark out the planting area and dig the holes, either one at a time or several at once. If the soil is dry, fill each hole with water and let it drain before setting in the plants. Push gently on the bottom of the cell to dislodge a plant, slide the plant out of its compartment without touching the stem, and set it in the ground. If the plant is at all rootbound, gently tease apart some of the roots, or encourage new root growth by cutting partway into the bottom of the root ball and pulling it apart a bit. Touching only the root ball and if necessary, the bottom leaves—not the stem—set the plant into the hole, firm the soil around it, and water well.

PLANTING A HANGING BASKET

Begin by filling the basket with potting soil to 2 inches below the rim. Set one or more plants in the center of the basket. Then plant several more around the edges, so they will cascade over the sides and disguise the pot.

For a fuller look, use a hanging basket made of wire. Line the inside of the basket with sheets of moistened sphagnum moss that you butt up against one another at their edges. Fill the basket one-third of the way with potting soil. Then insert some small plants around the sides, pulling aside or cutting through the moss so the plant tops are outside the basket, but their roots are planted in the soil. Add more soil mix to fill the basket two-thirds of the way, and add more plants. Then fill the basket the rest of the way, and plant the top as usual, with one plant in the center and three to five plants near the edge of the basket.

Baskets need to be watered daily in hot weather. To check whether a basket needs water without taking it down from its hanger, place your hand on the bottom and lift up so the pot rests on your hand. If it feels very light, the soil is too dry. When the pot has some weight to it, the soil is moist, and you don’t have to water.

PLANTING A WINDOW BOX

Window boxes are a delightful addition to your home. They add instant charm to a country cottage and beautifully soften the severe facade of a city brownstone. Annuals are the plants of choice for window boxes, offering practically limitless combinations of color, form, and texture.

Plan your window boxes before you buy the plants. You’ll want some taller and some shorter plants, plus some trailers. (See the list on here.) Choose colors that harmonize or contrast attractively with the colors of your home.

There are three ways to plant a window box: directly in the box, in a molded plastic liner that sits inside the box, or in individual pots that you place inside the box.

Plastic liners are the most convenient way to go, especially if you want to change the plants for different seasons. You simply pop the planted liner into the box. Liners are also easy to remove when the window box or the plants need maintenance.

If you plant directly in a wooden window box, be aware that constant contact with moist soil causes wood to deteriorate quickly. You can prolong its life by painting the inside of the box with polyurethane.

Planting in individual pots allows you to change plants during the season, but makes it harder to create a natural, gardeny sort of look. If you do keep the plants in pots, cover their tops with a layer of unmilled sphagnum moss.

No matter what kind of container you use, it’s important to provide drainage. Purchase metal boxes with predrilled holes or drill holes in the bottom of wooden boxes or plastic liners. Use screening or row cover material to cover the holes.

Hanging basket plants

• Cascading petunia cultivars (Petunia × hybrida)

• Edging lobelia (Lobelia erinus)

• Fuchsia (Fuchsia hybrids)

• Impatiens (Impatiens hybrids)

• Ivy geranium (Pelargonium peltatum)

• Nasturtium, trailing cultivars (Tropaeolum majus)

• Rose moss (Portulaca grandiflora)

• Sapphire flower (Browallia speciosa)

• Variegated vinca (Vinca major ‘Variegata’)

• Wax begonia (Begonia Semperflorens-Cultorum hybrids)

• Wishbone flower (Torenia fournieri)

Potting soils

When planting in containers, it’s best to use a light, porous potting mix. You can use a packaged preblended potting soil, as long as it contains a lightening agent such as perlite or vermiculite and is not 100 percent soil. Or you can mix 3 parts potting soil or topsoil with 2 parts crumbled compost or leaf mold, and 1 part perlite or vermiculite. If you prefer a soilless potting mix, buy one or make it by mixing equal parts of peat moss, perlite, and vermiculite.

CAREFUL TRANSPLANTING

1 Water first; then gently push the bottom of the cell pack to loosen the root ball. Rest the stem of the plant against your hand, but do not injure it by pressing on it.

2 Holding only the root ball, carefully lower the seedling into the planting hole. Fill in and press down gently to put the roots in contact with the soil. Water well.

Annuals for Window Boxes

• China aster (Callistephus chinensis)

• China pinks (Dianthus chinensis)

• Coleus (Solenostemon scutellarioides)

• Edging lobelia (Lobelia erinus)

• Flowering tobacco (Nicotiana x sanderae)

• Geranium (Pelargonium species)

• Globe amaranth (Gomophrena globosa)

• Heliotrope (Heliotropium arborescens)

• Impatiens (Impatiens hybrids)

• Madagascar periwinkle (Catharanthus roseus)

• Marguerite (Argyranthemum frutescens)

• Marigold (Tagetes species)

• Nasturtium (Tropaeolum species)

• Nemesia (Nemesia strumosa)

• Pansy (Viola x wittrockiana)

• Petunia (Petunia x hybrida)

• Plume-type celosia (Celosia argentea)

• Pot marigold (Calendula officinalis)

• Rose moss (Portulaca grandiflora)

• Salvia (Salvia species)

• Sapphire flower (Browallia speciosa)

• Snapdragon (Antirrhinum majus)

• Stock (Matthiola incana)

• Sweet alyssum (Lobularia maritima)

• Variegated vinca (Vinca major ‘Variegata’)

• Wax begonia (Begonia Semperflorens-Cultorum hybrids)

• Wishbone flower (Torenia fournieri)

• Yellow cosmos (Cosmos sulphureus)

• Zinnia (Zinnia species)

A romantic window box (opposite) overflowing with cascading petunias softens a brick facade. Red and white flowering tobacco add height to the planting.

PLANTING A WINDOW BOX

1 Clean used boxes thoroughly with a brush and then a 10 percent bleach solution.

2 Plant the tallest plants to the rear, the shortest in the front, and midsize plants between.

3 Water well, and fill in any low spots with extra potting soil. Shade until plants are established.

4. Keep plants watered, deadheaded, and trimmed to promote season-long blooming.

CARING FOR WINDOW BOXES

Because they contain such a small volume of soil, window boxes need frequent watering. You’ll need to water at least once a day in hot weather. Aim to keep the soil evenly moist but not soggy or waterlogged.

You’ll need to fertilize regularly, too. Water-soluble liquids, granular blends, and timed-release pellets are the easiest and most convenient fertilizers. Follow the package directions for quantities and timing. Fast-growing annuals will probably need fertilizing every two weeks or so, unless you use a timed-release fertilizer.

PLANTING LARGE CONTAINERS

When you plant a half-barrel or other large container with several kinds of plants, choose the plants carefully. Plan for a gradation of heights, like a miniature version of a garden bed or border, to create a sense of depth and a more interesting display.

For a full barrel, plan on buying three tall plants, four to six mediumheight plants, and eight to twelve small or trailing edging plants. The barrel may look a bit sparse when you first plant it, but it will quickly fill in. If you stuff a container too full of young plants, either the larger ones will soon engulf the smaller ones, or all of them will languish after a month or so for lack of space. If you plant so densely that you have an instantly overflowing container, plan to fertilize frequently throughout the growing season.

Before planting, place the container where you want it. Unless you put it on wheels, it will be too heavy to move once it’s planted. Make sure the drainage is adequate; drill holes in wooden containers and cover them with nylon screening. Fill the pot to within 3 inches of the rim.

PLANTING A LARGE CONTAINER

1 Plant the tallest plants (here, sunflowers) at the rear or in the center, depending on how the pot will be viewed.

2 Next, place the midsize plants (here, cannas) in front of the tallest ones or surrounding them.

3 Place the next largest plants (here, caladiums) either in front of or surounding the midsize ones.

4 Plant trailers (here, cascading petunias and sweet potato vines) at the edges of the pot to cascade over the sides.

By late summer, the sunflowers and cannas (planted above) will be in bloom, and the caladium, sweet potato vine, and petunias will be thriving.