How to Grow Zinnias for a Gorgeous Cutting Garden

Zinnias are among one of the best cut flowers for beginner and seasoned gardeners alike. There are hundreds, if not thousands of different varieties of zinnias out there, and for good reason! They make great cut flowers and bring beauty and a rainbow of color to any bouquet. An all around great choice for the cutting garden!

Growing Zinnias from Seed

Zinnias are incredibly easy to grow from seed. They can be started successfully indoors in plug trays 4-6 weeks before planting out. Just keep in mind they are heat-loving plants, so make sure to not start them too early. Young plants can be tucked into garden beds in late spring when all danger of frost has passed. They can also be sown directly into the soil. I have used both methods successfully!

Fertilizer and Good Soil

Most flowers prefer rich, well-draining soil that has been amended with some sort of organic matter and organic fertilizer. Zinnias are no different! I use compost in all of my cut flower beds, and prefer to use Espoma fertilizers and soil amendments when I do my initial planting of flowers. I also fertilize regularly throughout the growing season!

Common Pests + Problems

Zinnias are very prone to powdery mildew, especially in the hot and humid days of late summer. To combat this, make sure the plants are planted 9-12 inches apart to encourage good airflow between them. Good air circulation is key to preventing any of those pesky fungal spots that can begin to appear on the leaves. Making sure that the plants are well-watered and fertilized will also help minimize any disease pressure.

Japanese beetles also love zinnias, and can be quite destructive if left to do their thing without any intervention. They chew large holes on the leaves of plants, making the leaves look like lace.

When to Harvest

Zinnias require what is known as the “wiggle test” before harvesting. Place your hand around the middle of the stem and gently shake the zinnia. If the bloom droops and bends back and forth, it needs more time before harvesting! Zinnias should be sturdy on the stem and not move much- that’s when you know its the perfect time to cut. If you harvest them too early before they are ready, they will wilt in the vase. Use a pair of sharp pruners to make a cut at the base of the plant. Zinnias are known as a “cut and come again” flower, meaning they will continuously pump out new blooms even as you make multiple cuts on them throughout the growing season.

It is important to regularly harvest your zinnias. Be sure to deadhead any spent blooms to help focus the plant’s energy on producing new flowers and not going to seed.

Favorite Varieties

I personally love the Benary’s Giant series. They are huge, tall varieties that come in an array of vibrant colors. The Queeny series is also another beautiful collection, with unique antique color tones that are unlike any other flower I’ve seen. This year, I am trying out a collection of new zinnia varieties from Floret Originals!

Where to Buy Seeds

Some of my favorite online shops for buying zinnia seeds:

Quick Growing Tips for Success

All cut flowers do best when cut first thing in the early morning, before it gets too hot. If cut in the heat of the day, they are prone to wilting in the vase.
Place all cut flowers immediately into a bucket or vase full of cold, clean water.
When creating a cut flower arrangement, add some floral preservative to the water to help the flowers last longer.
Do some research into your average last frost date. This will help you know when is best to plant.
Zinnias like it hot and sunny. Be sure to plant them in full sun locations and provide plenty of water for best results.
Zinnias are very cold sensitive plants. They are annual flowers that typically will not last past the first frost of the year.
Be aware of pests! Zinnias (especially in the humid south where I garden) are prone to powdery mildew, particularly in late summer. All flowers are also prone to bug damage throughout the season.

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Floral Preservative
Snips
Liquid Fertilizer
Seed starting trays
Heat mat (good for encouraging germination when starting seeds indoors)

Natural + Effective Garden Must Haves

Over the years, there have been a few gardening staples that I have relied on to give me great success in the garden, while also keeping the garden free from chemicals that can harm us and our pollinator friends. Grab the FREE checklist here.

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Let me know what your favorite variety of zinnia is to grow. I’d love to know!