Cheerful zinnias are easy to grow
Zinnias are one of the oldest cultivated flowers, but still one of the greatest because they are fast-growing, easy-to-care-for, and add lots of color to the garden. Zinnias are one of the most cheerful flowers with their vivid colors and petals which range from rounded and squared to twisted and shaggy. The true testament to the durability of this annual is that many of the cultivars grown 50 years or more ago are still available and popular today. One example of this is Envy, which is the lime-green zinnia developed in the 1950s and is still coveted by gardeners and arrangers today.
Zinnias are easy to grow, but with a little extra care they will yield more and healthier flowers. To get zinnias off to a good start, choose a location with good air circulation and full sun. Zinnias will be floppy and sickly if you try to grow them in shade. They will tolerate a wide ride range of soil, but will reward you if they are planted in moist, well-drained soil that has a lot of compost worked into it. They also like a little fertilizer mixed in, or added to water if you water them, and will reward you by blooming all summer. Sow zinnia seeds directly into the soil in the spring about the same time you put out tomato plants, and by mid-summer you will have numerous blossoms.
Zinnias love the sun and will languish in cold weather. Dry conditions translate into healthier zinnias, so don't overwater. If you do water them, water the base of the plant, being careful not to get moisture on the foliage. Older varieties of zinnias are susceptible to powdery mildew. While powdery mildew will not kill the plant, it does disfigure the foliage and occasionally the flowers of zinnias. A couple inches of mulch or compost around the base of zinnias will help to conserve moisture.
Some of the new ideas in zinnias are what are called "dahlia-flowered," which means they have layers of petals. While most zinnias are one color, new varieties like Candy Cane are white with streaks or splashes of red color. Or Zowie! Yellow Flame, which has orange-red petals that look as though they have been dipped in gold. Such colorful zinnias stand out better if they are paired with solid color flowers that won't compete for attention.
Some of the new hybrid zinnias are only about 12 inches tall, have daisy-like flowers, and are great for edges or borders because they love the hot sun on a southerly exposure. The new hybrid zinnias are mildew resistant, and can be crowded into containers where they may not get the air circulation required of older traditional types. While some of the older traditional zinnias grew as tall as 4 feet, The newer hybrids are shorter and stockier, so they can better support their huge blossoms. They are also have more branches, so you need fewer plants.
Zinnia foliage is raspy and rough so that plants grasp onto each other and help hold each other up. However some of the older traditional tall zinnias may still need to be staked because they get top heavy.
One of the best things you can do to keep more flowers coming is to deadhead the faded blossoms. Or enjoy lots of flowers for bouquets, cutting just above a set of healthy leaves. In a week or two, you will find two more new stems sprouting from the spot, to give you more flowers.
Breeders are working to develop zinnias which are tough and extremely disease resistant. They are trying to develop larger flowers, and double flowers that hold their color longer. The newer plants will have more branches and spreading habits, so you can fill up a large space with fewer plants.
Kyle Schulz is a Wadena County Master Gardener from Sebeka, and the regular gardening columnist for the Wadena Pioneer Journal.