How to Plant, Grow, and Care For Cactus Zinnias

Cactus zinnias are large, colorful, and easy to grow! These flamboyant flowers make an excellent addition to the cutting garden and flower beds. Join gardening expert Melissa Strauss to learn about growing and caring for these exciting, long-blooming plants.

In an average summer season, I plant more zinnia seeds than any others by at least double. They are so easy to grow. And they provide a ton of color and personality to my flower beds and summer cutting garden. Of all the many varieties you can grow, cactus zinnias are some of the most colorful and flamboyant flowers around.

Zinnias come in a wide range of colors, sizes, and petal formations. Varieties span from the tiny but spunky ‘Thumbellina’ to the grand ‘Benary’s Giant.’ I could plant a whole bed of zinnias and never get tired of them.

The best thing about these plants is the amount of color and sheer volume of flowers they produce. One plant can produce dozens of flowers, even the larger cultivars! When it comes to big, flashy flowers, cactus zinnias are among the top contenders.
What Is It?
Cactus zinnias are a distinctive type of zinnia, characterized by their large and unique flowers. They’re sturdy plants with oversized blooms that come in a variety of bold, noteworthy shades. Horticulturists have developed these stunning cultivars from the Zinnia elegans species for their uncommonly beautiful form.

Characteristics
Cactus zinnias are large plants growing up to 40 inches tall. While they are not the tallest variety, they come reasonably close. They bloom from early summer until frost, producing a large number of flowers throughout that time.

The plants aren’t the only thing that is larger than average. Cactus zinnia flowers are among the largest of the species. The blooms span four to six inches across and come in a range of colors, including pink, white, red, orange, yellow, and purple.

The most noteworthy characteristic of this variety is the long, narrow, fringe-like petals. They aren’t named cactus for any relationship to an actual cactus. Instead, they’re named such because of how closely they resemble cactus-form dahlias.

These are fast growers, like most zinnias, and they don’t take long to bloom. About two months after planting, you should start to see developing buds. With proper care, they will bloom continuously. They have sturdy stems that are great for cutting.
Native Area
Cactus zinnias are hybrids, so this particular form is not naturally occurring. However, the species Z. elegans is native to Central and southern North America, particularly Mexico. They typically favor semi-arid climates.

Planting
Spring is the best time to start your cactus zinnias. These annuals love warm weather and are easy to sow in your garden beds directly. Although they offer a wider variety, these aren’t the best choice for container gardens, but they will grow well in larger raised beds.

Remember to leave ample space when planting to allow for spreading out. With proper tending, they can grow large and shrubby. Since the larger plants produce the most flowers, this is the desirable state.
How to Grow
Cactus zinnias are easy to grow, but flourish under a specific set of ideal conditions. Once they are mature and blooming, they are a joy to behold. They’re also an excellent food source for pollinators and other beneficial insects.
Maintenance
Deadheading is the most crucial maintenance practice to get into with your zinnias. The more you deadhead, the more the plant will branch. More branches mean more blooms.

When you deadhead, don’t just pop the flower off the top of the stem. Cut the stem all the way down to a node where another shoot is forming. This will keep your zinnias full and bushy, and producing more flowers.

Propagation
The most effective way to propagate zinnias is by seed. It’s possible to use cuttings, but it’s highly unreliable. The only reason to do this is to ensure that you have an exact clone of the parent plant. It often is ineffective, though.