All About Growing Zinnias: Easy Beautiful Summer Flowers

All about growing zinnias from seed. Enjoy these easy-to-grow, colorful flowers in your summer garden.

What is the first thing that comes to mind when you think of summer flowers? For me, it’s bright, colorful, cheerful blooms. And nothing fits that description better than zinnias.

You may remember earlier this year. I shared some tips on Preparing to Plant a Cut Flower Garden. Here I shared the first stage in my process for growing a cut flower garden from seed.

Later, in Sharing from the She Shed: Spring Gardening Inspiration, I shared my process for planting raised flower beds.

Now, my flower garden is in full bloom, and I am excited to share some tips with you about growing zinnias. These colorful flowers are easy to grow from seed and are low maintenance. They are an excellent choice for a beginner or seasoned gardeners to add an explosion of color to your summer garden.

Where do Zinnias Grow Best?

Zinnias can be grown in all zones in the appropriate season.

They grow best in full sun, so plant them in an area that will get at least 6 hours of sun each day.

I have planted mine in a raised bed and directly sowed seeds in the ground.

When planting in a raised bed, I mix potting soil with chicken manure and worm castings. This mixture produces very healthy plants.

Zinnias aren’t too picky about their soil, but ideal conditions are fertile and well-draining soil with plenty of organic material.

What Color Are Zinnias?

The zinnia flowers come in various colors and shapes, depending on the variety.

You can find zinnias in shades of orange, pink, purple, red, white, and yellow – almost every rainbow color! That’s one of the reasons zinnias are so versatile and can easily be worked into any summer garden. You can also find bi- and tri-color zinnias for even more variety.

There is a range of shapes of zinnia blooms that can be just as diverse. So when planning your garden, take some time to research different varieties to find the look you like best!

How Big Do Zinnias Grow?

The sizes of the zinnias vary significantly by type. For example, some tall varieties grow up to 4 feet and 2 feet wide, while dwarf varieties may only grow 6 to 12 inches tall and wide.

Use tall varieties in a cut flower garden, as a back border, or dwarf varieties in a front border or in containers.

How Long Do Zinnias Bloom?

Zinnias proliferate quickly and can begin to bloom as early as late spring. Blooms may slow down at the peak of summer due to the heat but will continue through fall until the first frost. For continuous summer blooms, plant new seeds every 2 to 3 weeks.

Do Zinnias Come Back Every Year?

Zinnias are an annual flower, meaning they do not come back yearly. However, if seeds fall, you may find you have a few in the garden next year.

These beautiful flowers are pretty easy to grow from seed. They also grow quickly and do not need much maintenance.

Growing Zinnias from Seed

Zinnias are best started from seed. They can be started indoors or sown directly into the soil outdoors.

When starting seeds indoors, use peat pots or other plantable containers so as not to disturb the roots when transplanting.

Zinnias do not tolerate frost, so wait to transplant seedlings or sow outdoors until the temperate at night is at least 50 degrees Fahrenheit when there is no further threat of frost.

Seeds should be planted ¼ inch deep in moist soil. Space seeds about 6 inches apart, with rows at least 12 inches apart, or follow spacing guidelines on the seed package. This will provide plenty of room to grow and allow for proper airflow.

With plenty of sunshine and water, seedlings should emerge in 4 to 7 days. You will see blooms on your zinnia plant in 6 to 8 weeks.

Growing Zinnias in Your Garden

Zinnias are an excellent addition to your summer flower garden.

Their bright and colorful blooms attract pollinators like bees. Hummingbirds, and butterflies, so they also work great near vegetable gardens or along walkways.

Zinnias are non-toxic to pets like dogs, cats, and horses, so you can feel safe planting them if you have animals that roam near your garden.

These flowers are also deer resistant and may even help protect other plants that are close by.

Zinnias look beautiful in many ways in your garden. First, create a border using different varieties in varying heights and colors. Dwarf varieties also work well along edging and in window boxes or containers.

How to Care for Zinnias

One of the great things about zinnias is that they are pretty low maintenance, but there are some tips I can share to help you get the most out of these beautiful summer blooms.

Pruning

If growing zinnias for cut flowers, taller varieties are ideal.

There is a proper way to prune zinnias to prolong flowerinFirst, snip the center flower when plants are about 18 inches tall. Pruning encourages plants to begin branching low, creating longer stems and more blooms.

Deadhead any spent blooms on your zinnia plants to encourage new growth.

Fertilizing and Mulching

If desired, fertilizer may be applied to encourage a more significant number and size of blooms, but it isn’t necessary.

Once zinnias are established, you may want to consider adding mulch on top of your soil. Mulch can help retain moisture and keep weeds from growing. Mulch will also break down throughout the season to form compost and provide additional nutrients to your plants.

Watering

Zinnias grow best in consistently moist soil, so they should be watered regularly, about 1 inch per week. Water at the base of the plant to keep foliage dry, which will help prevent diseases and keep your plant healthy.

Propagation

The zinnia flower seeds are easy to save. First, let the flowers dry entirely (on the stem), then remove by lightly crushing the dried seed head. Store in a cool, dry place, and they will be ready to use for planting next spring.

Diseases and Pests

There are a few diseases and pests that you may encounter when growing zinnias.

You may encounter spots, wilt from bacteria, fungi, or powdery mildew. You can prevent these diseases with proper spacing for good airflow and by keeping foliage dry.

If you find caterpillars on your zinnias, remove them by hand. Other common pests include mealybugs and spider mites, which you can spray with insecticidal soap.

Bring Zinnias Indoors

Please take full advantage of your gorgeous zinnias and bring them indoors to enjoy.

Their long, strong stems make them perfect for cut flower arrangements. Cut the stems at an angle above a bud joint and remove foliage before placing them in water.

Use a mixture of varying colors of zinnias to create a beautiful bouquet that truly embodies summer. The bright, cheery blooms pop against a classic white pitcher used as a vase.

Or, pair your zinnias with other warm-weather blooms like hydrangeas and peonies to create a unique summer bouquet. I love the varying shades of pink and purple in this beautiful arrangement. Finally, add individual elements like antique books and a wooden tray for a picture-perfect style to brighten your home.

Did you like this post, All About Growing Zinnias? Check out these related posts:

Everything You Need to Know About Growing Hydrangeas

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Preparing to Plant a Cut Flower Garden

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