You've just been notified of a cancellation on the home and garden tour and your garden has been chosen as a replacement. To add to the excitement, you have a little over a month to get it into full bloom. Don't panic: It's Annuals to the Rescue!
No other group of plants provides as much color as quickly and economically as annuals. True to their name, annuals sprout from seed, flower, set seed, and die within one season. There are many more plants that we treat as annuals that live longer in their native lands and in reality may be perennials, shrubs or even small trees. Get those beds ready first by adding three to four inches of organic matter such as compost, humus, pine bark, or peat moss and an inch or two of sharp sand if the soil is really heavy. If you are unable to get a soil test prior to the tour, you can simply broadcast two pounds of a slow-release 12-6-6 fertilizer containing minor nutrients per 100 square feet of bed space. Till it in with the organic amendments. Annual flowers can be grown from transplants or by direct seeding. But, if you need rescuing quickly, transplants are the way to go. The dilemma may be deciding which annuals to choose. Here are a number of great choices to consider.
Ornamental Sweet Potatoes (Ipomoea batatas)
The ornamental sweet potato has become a tremendous success story in just a few short years because it brings color and pizzazz to the landscape the entire season, and covers space almost as quickly as kudzu. Other than an insect or two, the ornamental sweet potato is foolproof. Whether cascading over a wall or trailing down a slope, you can't beat it. They often return from underground tubers. My favorites are the Sweet Caroline series and 'Margarita'.
Coleus (Solenostemon scutellarioides)
The coleus is a tropical plant and can certainly give a carnival-like atmosphere to the garden. The colors are richer, more highly variegated and many are now able to withstand full sun all growing season. New vegetatively produced varieties of coleus are vigorous, reaching 3 feet in height and width yet resistant to blooming, thereby providing non-stop vibrant colorful foliage from spring until frost. 'Plum Parfait', 'Burgundy Sun', 'New Orleans Red' and 'Mississippi Summer' are winning choices. The Solar series, with several variegated selections, is truly outstanding.
Lantana (Lantana camara and hybrids)
When it is August and the family has the thermostat turned to 67 degrees, few plants are showing off in the garden. But lantana is still going, and it has been remarkable since the first blooms of spring. In the southern U.S., you will find areas where the lantana is used as a perennial, tender perennial or annual. If you want lantana to provide instant color, consider buying a basket and planting it. Within a month or so, lantana will fill in nicely. Not only do hummingbirds feast on the nectar, the flowers are also virtual butterfly magnets. 'New Gold' is a consistent award winner, and 'Sonset', 'Miss Huff', 'Athens Rose', 'Samson', and 'Sonrise' are known for cold hardiness and outstanding bloom.
Castor Bean (Ricinus communis)
The castor bean is an old heirloom plant that produces huge colorful palmate leaves, giving the landscape the look of the tropics. It is treated as an annual in most locations, yet it can put on astounding growth, reaching eight to 10 feet in just one season from seed. Buy a plant in a gallon container and you will be surprised at the height and width in one month of growing. Red stems and burr-like seed pods are equally attractive. The castor bean is often sold generically. 'Red Spire' and 'Scarlet Queen' are popular named selections.
To Cover a Medium-Large Space Quickly
Begonia (Begonia x hybrida)
The 'Dragon Wing' has changed begonia growing for most of the gardening public. Large panicles of scarlet or pink blooms cascade downward from lush, glossy green angel-winged-shaped foliage. The plant grows with an incredible vigor, reaching three to four feet in width and blooms from spring until frost. It's one of the best buys in annual bedding plants.
Petunias (Petunia x hybrida)
The petunia wasn't a flower that was considered tough until the mid 1990s. This changed with series like the Wave, Surfinia, and Supertunia. These new vigorous, spreading plants now give the gardener petunias that will probably bloom from spring through frost. Some are showing remarkable cold tolerance, allowing them to either bloom during the fall and winter, or return in the spring.
To Cover a Medium Space Quickly
Melampodium (Melampodium paludosum)
The melampodium is the ideal beginner plant. It grows like it is on steroids and produces small bright yellow daisy like flowers from spring through frost. The plant is self cleaning, needing no deadheading, and thrives in the heat and humidity of summer as long as the soil is well drained. Look for varieties like 'Derby', 'Million Gold', and 'Lemon Delight', which are the leading compact varieties. 'Showstar' and 'Medallion' are choice taller selections.
Gloriosa Daisies (Rudbeckia hirta)
The gloriosa daisy is normally considered an annual, although they do return occasionally. Re-seeding is likely to occur, however, giving a perennial-like performance. During the summer growing season this will no doubt be the prettiest plant in the garden with brilliant golden yellow softball sized blossoms on 18-inch stems. Look for 'Indian Summer' or 'Prairie Sun'. These varieties reach close to four feet in height with a two- to three-foot spread. For this one to work in your short time allotment, start with a large plant that has just started to form buds.