Zinnia Flower Seeds

About Zinnia Flower Seeds

Zinnias are the easiest cut flower to grow from seed: quick to germinate, quick to bloom, and more productive the more you cut. They carry a border through the hottest part of summer and keep going until frost.

When to plant

Direct sow after all danger of frost has passed and the soil has warmed to about 70°F. Sowing a second and third batch two to three weeks apart keeps fresh flowers coming into autumn. Indoor starts are possible four weeks before last frost, but zinnias resent root disturbance.

Where to plant

Give them full sun and room for air to move — crowded zinnias are the ones that get powdery mildew. Any average, well-draining garden soil suits them; overly rich ground produces leaves at the expense of flowers.

How to plant

Sow a quarter inch deep and keep evenly moist until seedlings appear, usually within a week in warm soil. Thin to nine to twelve inches apart. Pinch the central stem above the third set of leaves to get branching plants with more, longer stems.

How to care

Water at soil level and avoid wetting the foliage. Cut or deadhead often: every stem removed brings more buds. For arrangements, cut when the stem is firm just below the flower head, ideally in the cool of the morning.

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