Zinnia Care Must-Knows
Native to grassland areas, zinnias are tough plants that handle drought well. Even though they grow best in well-drained organic soil, zinnias are extremely tolerant of poor soils, including hard clay. No matter where your zinnias grow, they will benefit from a slow-release fertilizer and the occasional liquid feed to keep them blooming all season long. This is especially true in container settings filled with a soilless potting medium. Because they come from prairie settings, zinnias prefer full sun. This environment nurtures the best bloom development. It also helps keep plants dry, which prevents common diseases such as powdery mildew—a condition most commonly seen as a white powder found on the plant’s bottom leaves. While this pesky fungus probably won’t kill the plants, it does diminish their beauty. The best control method for powdery mildew is prevention; look for resistant zinnia varieties and keep plenty of airflow around the plants. Leaf spot and blight are two more common diseases found in zinnias. Similar to powdery mildew, these conditions are caused by fungi. Control methods are the same: Remove any debris from the base of the plants to keep them clean. Many of these fungal diseases are found on the lower leaves of taller zinnia varieties used for cut flowers. Place shorter plants in front of taller zinnias to hide their naked stems. Saving zinnia seeds is a good way to start next year’s plants. Because many zinnias are sold as mixes, you don’t have to worry about seedlings being identical to the parent plant. As old flower heads dry, remove spent blooms and harvest the small arrowhead-shaped seeds from between each of the petals. Zinnia seeds can be started directly in the ground the following spring.
More Varieties of Zinnia
‘Benary’s Giants Orange’ Zinnia
Zinnia ‘Benary’s Giants Orange’ is an excellent cut flower with large, 4-inch-wide, double orange blooms. It grows 38 inches tall and 2 feet wide.
‘Magellan Mix’ Zinnia
Zinnia ‘Magellan Mix’ bears double blooms in a wide range of shades including red, pink, yellow, orange, and white. It grows 16 inches tall.
‘Parasol Mix’ Zinnia
Zinnia ‘Parasol Mix’ bears fully double, petal-filled flowers in a range of shades. It grows 12 inches tall.
‘Cut and Come Again’ Zinnia
Zinnia ‘Cut and Come Again’ is especially free flowering and bears double flowers in a range of bright colors on a 4-foot-tall plant.
‘Profusion White’ Zinnia
Zinnia ‘Profusion White’ is an early-flowering selection with good disease resistance and white flowers all summer long. It grows 18 inches tall and 10 inches wide.
‘Scarlet Flame’ Zinnia
Zinnia ‘Scarlet Flame’ offers double red flowers on a vigorous, 42-inch-tall plant.
‘Zahara Coral Rose’ Zinnia
Zinnia ‘Zahara Coral Rose’ bears big flowers in a soft shade of pink. It’s a disease-resistant, heat-loving plant that grows 18 inches tall and wide.
‘Zahara Starlight Rose’ Zinnia
Zinnia ‘Zahara Starlight Rose’ is a compact (to 18 inches tall and wide), award-winning selection with white flowers that have a distinct pink blush. It’s very disease-resistant.
‘Zahara White’ Zinnia
Zinnia ‘Zahara White’ is a compact selection (to 18 inches tall and wide) with big white flowers. It’s a disease-resistant, heat-loving variety.
‘Zahara Yellow’ Zinnia
Zinnia ‘Zahara Yellow’ produces big flowers in a bright, bold color on a disease-resistant, heat-loving plant that grows 18 inches tall and wide.
Zinnia Companion Plants
Spider Flower
It’s amazing that the tall, dramatic spider flower is only an annual. Once temperatures warm up, it zooms to 4 feet or more, plants very quickly, and produces large balls of flowers with fascinating long seedpods that whirl out from it. Cut it for vases, but be aware that the flowers shatter easily after a few days. It typically self-seeds prolifically, so you only have to plant it once. Because it develops surprisingly large thorns, it’s best to keep spider flower away from walkways. Plant established seedlings in spring after all danger of frost has passed. Cleome does best in moderately rich, well-drained soil. Be careful about fertilizing or you’ll have extremely tall floppy plants. Group in clusters of 6 or more for best effect.
French Marigold
Just as you’d expect from something called French, these marigolds are the fancy ones. French marigolds tend to be frilly and some boast a distinctive “crested eye.” They grow roughly 8-12 inches high with a chic, neat, little growth habit and elegant dark green foliage. They do best in full sun with moist, well-drained soil and will flower all summer long. They may reseed, coming back year after year, in spots where they’re happy.
Salvia
There are few gardens that don’t have at least one salvia growing in them. Whether you have sun or shade, a dry garden or lots of rainfall, there’s an annual salvia that you’ll find indispensable. All attract hummingbirds, especially the red ones, and are great picks for hot, dry sites where you want tons of color all season. Most salvias don’t like cool weather, so plant them outdoors after all danger of frost has passed.
