Many annuals and tender perennials make excellent plants for container gardening. Grown in pots, window boxes, or even a pair of old boots, container plants can transform any area of your home or yard.
Though hardy perennials, shrubs, and even trees may be grown in containers, keeping them healthy for many years requires special care.
Seek advice at a local nursery if you’re interested in this type of container gardening.
Nurseries and garden centers carry an excellent selection of annuals and tender perennials that grow well in containers.
Choose from pansies, petunias, snapdragons, cockscombs, lobelias, geraniums, daisies, spike plants, and dusty millers.
Finding attractive containers is part of the fun. Buy containers, or use a favorite pot or un-usual found object.
Make sure the container has draining holes; if not, drill 1/2-inch holes in the bottom. Potting soil should have a crumbly texture and retain moisture without becoming soggy.
While it’s possible to make your own, many gardeners get the best results by purchasing bagged potting soils.
Most types work well for annuals and tender perennials. You can display one plant or many in a single pot. Don’t be afraid to crowd a pot.
Dense displays look better than sparse ones, and commonly used container plants perform well when filled if well-watered and fertilized.
Good container combinations mix colors, textures, and heights just as in gardens, but on a smaller scale.
Begin by moistening the soil mix until it is damp. Add some slow-release fertilizer if you wish, in recommended quantities.
Place screening or old nylon stocking material over the drainage holes, and fill your pot within 2 to 3 inches of the rim.
Insert the plants into the soil, working from the center out. Keep individual root balls as intact as possible, but disentangle roots that have wound around themselves.
The root balls’ tops should be about 44 to 1 inch below the rim of the pot. As you add plants, fill them in with potting soil. Then water the pot deeply.
You can start annuals and perennials from seeds or purchase plants from a nursery or garden center.
Starting from seeds is less expensive than buying plants but takes more time and effort.
Many hybridized perennials must be purchased as plants because seed-grown plants may not produce the desired characteristics.
Such plants are usually produced commercially by root division or stem cuttings.
Annuals and a few perennials are sometimes sown directly where they are to grow; in fact, some plants do best when direct-sown.
Seed packets are dependable sources of basic information on planting—when and how deep to plant and how long until germination.
STARTING SUMMER-BLOOMING BULBS AND TUBERS
The bulbs and tubers of lilies, dahlias, gladiolus, cannas, and similar plants can be planted directly into the garden or started indoors in pots for later transplanting.
In cold-weather climates, tender summer-blooming bulbs such as gladiolus and dahlias are planted in spring each year.
Lilies are planted in spring or fall. Plant bulbs or tubers in the garden after the danger of frost has passed.
Be sure to plant them at the depth recommended by the supplier, and don’t let the soil dry out while they are sprouting underground.
Plant as many bulbs or tubers as you want plants.
To get a head start on bloom time, plant bulbs or tubers indoors a few weeks before the last frost—plant in 4-inch pots, using one bulb or tuber to a pot.
Keep the potting soil wet at all times. When shoots or leaves appear, put the pots in a warm, bright window or under lights.
Water and fertilize regularly as the plants grow, and carefully transplant the started plants into garden beds or display containers after all danger of frost has passed.
Gardeners in cold-winter areas will need to dig up tender corms and tubers in the fall and store them indoors.
When you place these plants in a garden bed in the spring, be sure they’re accessible and positioned so that the fall digging won’t disturb neighboring plants.
Some gardeners prefer to grow tender bulbs in separate beds or cut gardens or replace them annually because of this disruption.
Transplanting to the garden is a simple procedure, as long as you follow a few guidelines.
Always space the plants according to their mature size, following recommendations. You can fill the spaces between slow-growing perennials with annuals for the first one or two seasons.
Ensure the annuals are shorter than the perennials so that they don’t retard the perennials’ growth.
Water is crucial for new plants. If nature doesn’t oblige, provide an inch per week throughout the growing season—even for drought-tolerant plants—until they are established.
Mulch around the plants to retain water, keeping the mulch back from the stem to avoid disease problems.
Transplanting outdoors during the summer can be hard on seedlings. Cover them with a shade cloth, or erect a temporary lath house for filtered light.
There are various ways, aside from starting seeds, to increase your perennials. The easiest method is division.
Many perennial plants form a dense concentration of stems, called a crown, at their base as the number of stems increases each year, the plant increases in diameter.
You can produce two or more new plants from a single plant by dividing the crown and its attached root and top growth.
Some plants, such as daylilies, hostas, and irises, have thick stems and roots that are easy to imagine as separate plants when you look at the root ball.
Other plants, such as yarrows, asters, and Shasta daisies, have finer roots and stems that appear as a more or less undifferentiated mass.
Nevertheless, they will form new plants when divided. Although small plants can be divided, you’ll get a better show more quickly if you divide mature plants into several good-size clumps.
Disperse perennials in the early spring or early fall. In cold-winter climates, spring division offers new plants a full growing season to become established.
In mild-winter climates, fall division provides months of mild weather for the establishment and avoids subjecting divisions to hot, dry summer weather.
Before you divide plants, prepare the areas where the divisions are to be transplanted.
The division isn’t always done to increase your plants. Some perennials become unhealthy when they grow too large. Division rejuvenates these plants.
From the last days of winter to the first days of summer, few home landscape elements are appreciated as much as spring-flowering bulbs.
This is particularly true in cold-winter areas where early bulbs such as windflowers, crocuses, and daffodils mark the seasons’ changing.
In warm-winter gardens, freesias and paperwhite narcissus provide a fragrant accompaniment to less dramatic but no less welcome seasonal changes.
Gardeners everywhere can sprinkle spring color near an entryway through a woodland garden or across a grassy hillside with little effort.
And spring-flowering bulbs are undemanding. Some go years after planting without attention.
Others need just a bit of fertilizer each year and, when a clump gets too crowded, division of the increased cache of bulbs and distribution of this bounty elsewhere on the property.
What a Bulb Is … and Isn’t
What we commonly call bulbs are actually several kinds of structures. Some are true bulbs (daffodils, tulips), others freesias) or tubers (windflowers, winter aconites).
All three are that store food for the production of roots, leaves, stems, and flowers.
Botanists note differences between bulbs, corms, and tubers, and they don’t always agree about classification.
Fortunately, these differences aren’t important when it comes to choosing and growing the plants.
For simplicity’s sake, we’ll refer to all three as bulbs in the general discussions that follow.
For gardeners, it’s helpful to know that all the food the plant needs to grow roots and shoots is stored in the bulb, corm, or tuber and that plants need to replenish this supply each year after flowering.
Each year, most bulbs, corms, and tubers reproduce themselves so that a single plant will form a small patch over time. Different of the plant are corms (crocuses, fleshy structures.
Bulbs can create almost any atmosphere, from formal to casual. Choose colors and forms carefully, and follow the guidelines below.
- Create a visual bouquet by planting bulbs in bunches (groups of 6 to 15 or more) than in single-file straight rows. To make the planting look more natural, group the bunches in free-form drifts that intersect each other.
- Plant some early-blooming bulbs, such as snowdrops, crocus, and glory-of-the-snow, in sunny spots by entrances or view of windows so that you can enjoy them when it’s still too chilly for strolls around the garden.
- Don’t be bashful about color. There’s not much competition for attention in the spring garden, so plant reds, yellows, oranges, soft peaches, pinks, and lavenders to enliven the scene. If you’re ambitious, you can coordinate colors in different parts of the season, changing your garden’s look in the space of a few months—for example, from pale blue, yellow, and white through lavender, pink, and peach to hot red and orange.
BULBS IN WARM-WINTER CLIMATES
Many spring-flowering bulbs (crocuses, tulips, and hyacinths, for example) require a period of cool temperatures to grow and bloom well.
In areas where winter temperatures don’t fall below 45°F for extended periods of time, these bulbs can be a disappointment.
Some warm-winter gardeners grow these plants as annuals, buying fresh bulbs each year from suppliers that prechill them before shipping in the fall.
Gardeners wishing to recycle their own bulbs must dig them up and prechill them for several weeks in the refrigerator, a considerable task if you have many bulbs.
Fortunately, there are many fine winter-and spring-blooming bulbs that warm-winter gardeners can grow without the prechilling fuss —freesias, paperwhite narcissus, ranunculus, cyclamens, and alliums.
If you’re uncertain about which bulbs grow well in your climate, ask at a local nursery.