Growing Zinnias From Seeds

Zinnias are native to Mexico. Because of that, they really perform well in hot, full sun. All you need to do is plant them about a quarter inch deep in well-drained soil. Because they grow so fast (under the right conditions), there’s not really any need to start them indoors unless you have a short growing season. I’ve planted zinna seeds and had blooming plants 5 weeks later! You can also continue planting more seeds throughout the summer for even more consecutive blooms. 

You’ll see seedlings sprout in 5-10 days. Though under sunny, warm conditions, I’ve seen seeds germinate as quickly as 2-3 days! Once the seedlings reach about three inches tall, thin them so that they’re 6 to 18 inches apart to maximize air circulation, a key to keeping zinnias looking good all season. 

I usually remove the first blooms, which encourages the plant to produce more flowers. The more blooms you snip from zinnias, the more flowers they produce.

A few notes from my experience growing zinnias.

-If they are planted in the shade or even partially shaded, they will either not germinate or grow very slowly. It’s best to keep them in direct sunlight all day.

-A garden with deep, rich, loose soil will produce the best plants. If your soil is “dense” or lacking organic matter, they may struggle.

-I’ve found it’s fairly easy to dig up a seedling and relocate to a different spot. This is helpful if you have too many seedlings in one area or later discover they have been planted in a less than ideal location. 

-Water at the base of the plants to keep them free from leaf disease.

-They last a week in a vase! So you have plenty of time to enjoy your beautiful blooms.

-I do a run of Miracle Grow sometimes once a week in their peak blooming period for maximum growth and flower size.

-Zinnias are not frost hardy, so they will die off in the cold weather.

-To create bushier plants on tall varieties, pinch the growth tip of the plant when young. This will stimulate more side branching, a shorter plant, and more flowers.

© Copyright Terry Aley

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