Growing Zinnias From Seed For Beginners

Zinnias are a summer garden staple for good reason. They come in a wide range of colors, bloom all summer long, and are easy to grow. Even beginners can grow loads of beautiful zinnia blooms. Plus, bees and butterflies love them so they are perfect for pollinator gardens! Keep reading to learn how to grow zinnias from seed.

Types Of Zinnias

Zinnias are annual flowers that grow in full sun and well-drained soil. They thrive in heat and tolerate drought well. Zinnias range in height from 6 inches to over 4 feet tall. Their flowers can be striped, speckled, or solid in a variety of colors from pastel to vibrant hues. 

Zinnias also come in an array of flower forms. These include single bloom, beehive, button, and cactus. They make wonderful cut flowers that can last in a vase for a week or more. And, if deadheaded, they can bloom from early summer until frost. But we’ll talk about that later!

How To Plant Zinnia Seeds

Zinnias prefer direct sowing in the garden, but you can start seeds indoors and transplant them later. Start zinnia seeds in peat pots or another form of biodegradable pot. When seedlings are a few inches tall, plant zinnias and pots in the garden to avoid disturbing seedlings’ tender roots.

The easiest way to grow zinnias from seed, however, is to plant them straight into the garden. Spacing depends upon the variety you wish to grow. Look at the back of your seed packet for instructions specific to your type. Once all chance of frost has passed, plant zinnia seeds in well-draining soil. Lightly cover the seeds with soil and give them a good drink. Keep soil moist, but not soggy. Zinnia seeds should germinate in 5 to 10 days.

How To Care For Zinnias

Some zinnias benefit from staking. Use garden supports to keep tall zinnia varieties from flopping over. Plant them next to a trellis, mailbox, or lamppost or create your own zinnia supports with strong vertical stakes and twine. Weave twine into a grid when plants are still small and zinnias will grow right through. 

Deadheading helps zinnias bloom all summer long. Once flowers fade, cut or pop the heads off your zinnias. Cutting flowers for bouquets also prolongs blooming. Succession planting is another way to extend zinnia blooming. Starting in late spring, plant zinnia seeds in the garden every two weeks until mid-summer to ensure fresh blooms through fall. Another option is to let faded flowers remain and go to seed, then save the seeds to grow in next year’s garden. 

Zinnia Diseases And Pests

Zinnias are very low-maintenance, however, they can encounter some problems. Common zinnia pests include spider mites, grasshoppers, and bud worms. Zinnias can also develop powdery mildew but, thanks to breeders, many new cultivars like the ‘Magellan’ series are more resistant to this problem. To prevent problems, avoid overhead irrigation and water early in the day to keep foliage dry. Space plants far enough apart to allow for good airflow to keep plants happy and healthy.