Zinnias are a sure thing in the garden world. Why? Not only do they do well in less than sufficent soil, but they need little care and can withstand most pests, diseases, and drought. Reputation aside, zinnas are a colorful delight -- bursting with bright colors. Whether pale peach, vivid violet or sizzling scarlet, zinnias are a festive annual.
Native to the United States, zinnias come in a medley of shapes and sizes. Some zinnias are delicate and dainty at 6 inches tall with round flowers less than an inch across. Others are grand and imposing, stretching to a height of three feet and boasting 7-inch blossoms on strong, wiry stems. Crosses between these two types are known as interspecific crosses. Zinnia flowers may be single daisywheels, double blossoms, cactus-like with plumed rays, or anemone-like with broad, spreading rays.
Zinnias Work in Many Places
Try small to medium zinnias in containers. They make great companions to asparagus fern, licorice plant, and petunias.
Small zinnias make eye-catching borders for summer annuals. They're great for perking up your late-summer garden when most annuals have been spent.
Get creative with medium-height zinnias in colorful bedding schemes. Zinnias blend well with flowers of similar shape, such cosmos and dahlias. It's also fun to try contrasting zinnias with spiky-flowered annuals like the salvia.
For cutting, tall zinnias are an excellent choice. They'll be happy when grouped between flowers like blackeyed Susans and cosmos in a sun-drenched bed.
Developed over the last decade, interspecific crosses have won faithful fans for their low-maintenance care and durability. They blend the luscious colors of garden zinnias with the hardiness of spreading zinnias. Two great choices are the brilliant orange profusion and the cherry profusion, which boasts an abundance of semi-double cherry rose flowers.
The spreading zinnias (Z. augustifolia), with their delicate, 1 to 2-inch wide flowers and elegant narrow leaves, are another garden favorite. They are both disease and weather resistant. Reaching 8 to 18 inches in height, spreading zinnias are ideal for annual ground covers and also make snazzy hanging baskets.
Old Mexico offers masses of overlapping pointed copper petals tipped with gold. This variety is easy to grow: simply sow outdoors once the soil has warmed. Old Mexico makes for charming country arrangements in earthenware vases.
The timeless classic zinnia features radiant orange, daisy-like flowers that are 1.5 inches wide. Weather resistant and able to flourish in poor soil, this zinnia is a perfect choice for containers.
Want a real showstopper? Try the large-flowered varieties of the zinnia family. They are also a snap to grow and bloom profusely throughout the season. Garden giant blooms in bursts of pink, rose, yellow, red, and cream on medium sized plants. These are great at the edge of beds or for cutting flowers.
How to Grow Zinnias from Seed
Zinnias thrive in all but very wet soil and they love plenty of sunlight. What's the easiest way to plant zinnias? Sow them right into your garden. While zinnias are virtually disease-free, one thing to watch for is powdery mildew, especially if you live in a high-humidity zone or in northern areas. If you live in a warmer climate, a single planting may not make it until the first fall frost. A tip: Keep sowing those zinnias every two weeks or so through early July to make sure you get to enjoy endless blooms.
Once you plants your seeds, they should germinate in one to two weeks at temperatures ranging from 70 to 80 degrees. In warmer temperatures, the germination time may decrease to as few as three days. Blooming will occur anywhere from 75 to 90 days.
Space them about eight to 12 inches apart, depending on height. Allowing extra space where diseases are a problem is a good idea; increased air circulation is a preventative. Water your zinnias with a soaker hose or drip irrigation to avoid getting the foliage wet.
Get rid of plants producing flowers with high centers surrounded by only one or two rows of petals. Old flowers also need to be removed to encourage continued flowering. If your plants seem to be growing slowly and their leaves look pale, a soluble or controlled-release fertilizer may help move them along.
Mildew can be a problem for susceptible plants such as garden zinnias. In warm climates, rainy or humid weather can also contribute to mildew. In cooler areas, mildew can attack in late summer or fall when moisture condenses on the leaves at night. Slow the spread of mildew by spraying affected plants with a baking soda solution (one half of a teaspoon of baking soda in two quarts of water with a squirt of liquid soap) or try an organic fungicide.
Zinnias are rarely troubled by insects, but every now and then, Japanese beetles, mites, and aphids may appear. Insecticidal soap is good for mites and aphids, so are beneficial insects like ladybugs and lacewings.
Lynn Parramore, a doctoral candidate in English, has written feature articles for the Prague Post, the Washington City Paper, and the Journal of Common Sense. Her favorite flower is the gardenia.