Zinnias are popular as a stand-alone plant, or can be used as a complementary addition to a complete flower garden design. The plants are native to North America, and are less finicky about soil and water than many plants of the same type. They do require some maintenance, however, and are not self-cleaning. This means you'll have to prune back the blooms after they have died, giving you ample opportunity put back some seeds for future plantings. Here are some ideas on where to plant zinnias in your garden.
Where you place zinnias for flower bed planting depends on what variety of zinnias you plan to use. Some varieties are petite, standing only about 6 inches tall, but other varieties maybe reach 2 foot or more in height. Be sure to plan for the size of your plants, so that your zinnias don't crowd out flowers that are growing behind them.
Zinnias are great for border planting. Because they're not especially picky about the soil, they do well along fences, where the soil quality may differ considerably along the same line. If you are not certain of the soil quality, using zinnias for a fence border or along the front of the house is a good idea. This provides color throughout the summer, and has the added benefit of being a wonderful attractor for butterflies.
Tree or Garden Borders
To protect their health, trees should have a protective border that is approximately equal to the diameter of the crown. Many home gardeners use the zinnia to define the outer edge of that border, because they're full and colorful, and the foliage grows at just the right density to create an effective border.
The zinnia is not finicky about the soil it grows in, but it will be healthier and stronger if you take the time to condition the soil before planting. Mix 1 part sifted compost with every 3 parts of existing soil, along with a sprinkle of gypsum. After conditioning the soil once, you can keep it healthy by adding sifted compost beneath each new distribution of mulch, allowing the nutrients to slowly work down through the soil naturally.
Zinnia Water Requirements
One of the most common errors with zinnias is over-watering. The zinnia does well in moist soil, but not in wet ground. Another danger with soil that's too wet is that it promotes the growth of bacteria and plant diseases, and can result in your zinnias becoming sickly or infected.
Avoiding Pests and Disease
The best way to keep a zinnia healthy is to keep the soil it grows in healthy. If you have problems with fungal growths, mix 1 tablespoon of baking soda with a quart of water, and use it on the soil beneath the plants. Avoid watering the plant leaves, as it may encourage bacterial growth.
To avoid insects eating your zinnias, complement your garden with ladybugs or praying mantis. These carnivorous insects will live on aphids and mites, two of the most common insect pests you'll have to worry about with zinnias.