By Guest Author Dayton Kingery
Zinnias are one of the easiest flowering annuals to grow, bringing bright, joyful, plentiful color to any garden. Their blooming is reliable, with flowers in bloom from late spring right up until the frost begins in autumn. With their minimal maintenance needs, and the copious variety of hues, sizes, and shapes, zinnias make a great choice for your backyard or garden.
There are 3 types of zinnias
Zinnias fall into 3 categories, based on their flowers:
- Single-flowered zinnias have a center surrounded by one row of petals, making it look almost like a daisy
- Double-flowered zinnias (aka fully double flowered) have several rows of petals that cover the center completely
- Semi-double-flowered zinnias have a visible center surrounded by layers of petal rows
There are many varieties and colors of zinnias
Zinnias are perfect for any sunny spot in your garden where you want to infuse color. With names like ‘Pop Art’, ‘Star Orange’, ‘Green Envy’, ‘Persian Carpet’, and ‘Candy Cane’, the blooms come in many hues. One can choose from pink, red, orange, purple, white, and yellow—or any combination of two or three of these colors.
Zinnias are also characterized by their shapes and heights. Zinnias can flower in star, daisy, dahlia, quill-cactus, button, spider, and dome shapes. The taller kinds, like Zinnia elegans, are more appropriate for a garden background. Shorter types, such as the Thumbelina and dwarf zinnias, are great for borders, edgings, and even window boxes. Mid-height zinnias, those in the Magellan and Zahara series, grow to be about knee-tall. The blooms are tolerant of all kinds of weather and last from summer to fall.
When to plant zinnias
Wait to plant zinnias until after the threat of frost has passed in your area – zinnias will not tolerate a spring freeze. This date varies by location so it is critical to know the last frost date for your area. If sowing seeds outdoors, do so in several sequences, with generous amounts of seeds each time. Doing this over the course of several weeks will provide blooms well into fall.
Zinnia seeds should be planted 1/4 inch deep in the soil. The spacing of the plants depends on the variety you are planting, so read the seed pack for the specifics. Seedlings should emerge within 10 days if the soil is warm and blooms generally follow 60 days later, depending on variety.
Where to plant zinnias
Once you have determined when you will plant your zinnias, you need to think about where you will put them. Zinnias need full sun and ample air movement to resist fungal diseases. The soil should have sufficient organic material and have adequate drainage. Compost added to the soil can add organic material and gently feed the flowers, encouraging abundant blooms.
Starting zinnias from seed
Zinnias transplant easily and can be started indoors from seed 6-8 weeks before your last frost. See our post on starting plants indoors.
Caring for Zinnias
Zinnias only need compost after planting and need little in the way of fertilizer. If your soil is healthy, the zinnia will have enough nutrients to bloom until frost. Zinnias can withstand periods of drought, as they’re native to the southwest U.S., Mexico, and Central America. But for optimum results give them one inch of water per week in the absence of rainfall.
You can encourage zinnias to branch and produce more flowers
When zinnias reach between 8 and 12 inches (20 to 30 cm), snip 3 or 4 inches off the top, right above a top set of leaves, with sharp pruners. This will signal the plant to produce multiple stems below the cut, yielding abundant flower production and elongated stems. Deadheading, or removing old flowers, facilitates the formation of new zinnias. After blooming, if you let the seeds dry fully on their stem, you can save the zinnia seeds for planting the following spring.
Helping zinnias avoid disease
Zinnias are prone to bacterial and fungal infections like powdery mildew and wilt. Sufficient airflow between plants can help discourage these diseases.
When the seedlings are about 8 inches tall, make sure they’re 6-12 inches apart (depending on variety). If they’re too close, thin or transplant the seedlings so they have sufficient airflow between them. Spraying zinnias against mealybugs, mites, and caterpillars is not necessary unless infestation is significant and leaf damage is substantial.
(Even) More Reasons to Plant Zinnias
- Deer do not like zinnias. Zinnias are also not toxic for most household pets, so you won’t have to worry about your furry friends taking a bite.
- The bright colors of zinnia flowers make them particularly attractive for bees, butterflies, and hummingbirds. The combination of dazzling zinnia colors and animated butterfly activity is certain to bring cheer and spirit to your garden.
- Zinnias are relatively carefree. Simply compost after planting and let them grow.
- Zinnias are symbolic of absent loved ones. They are a great choice for a memorial garden and the perfect way to remember friends and family. The flowers’ lively and cheery growth is ideal for keeping those you love in your heart and mind.
- Zinnia cuttings are great to include in indoor floral arrangements. Their strong, long stems and jovial colors will raise the wow-factor of any bouquet. Add a teaspoon of bleach and sugar to the water to prolong the flowers’ vibrancy in a vase. Smaller, narrow-leafed zinnias can be planted in outdoor hanging baskets and then brought inside for a beautiful bunch of dried flowers.
- Originating in desert locations like the southwestern United States, Mexico, and Central America, zinnias can withstand harsh heat. This means that even in the dead of summer, your garden can be bright and blooming with zinnia flowers.
- Zinnias are edible! While on the bitter side, they make a colorful and whimsical addition to a green salad.
Overall, zinnias are the kind of plants that check several boxes: they are bountiful, beautiful, and easy. They are the type of flower that is hard to NOT include in your garden, as they add so much color for very little work. Perhaps the hardest part of including zinnias in your yard will be deciding which kinds you want to grow…and an exciting aspect of annuals like zinnias is that you can experiment each year.
Author’s Bio: Ever since hiking through Connecticut’s portion of the Appalachian Trail as a young boy, Dayton Kingery has been passionate about hikes, plants, gardens and all things related to nature. His passion was fueled by living in a state with so many wonderful national parks, trails, and gardens. Dayton is the founder of BusyBodies365 which is dedicated to the pursuit of a healthy and active lifestyle.
We garden in Pennsylvania, United States, zone 6B. Much of the info we share is based on gardening in our temperate area. But many of the flowers, vegetables, and fruit we write about can be grown in soil other than ours (clay) and significantly different weather conditions and elevations. You might need to choose specific varieties for your region, modify your garden, add soil amendments, or adjust the soil pH to match our results. Please check your local university extension website for specifics for your area.