Watering Sunflowers for Maximum Seed Production

When watered correctly, sunflowers can be drought tolerant and productive. Here are our tips:

Watering Sunflowers. With larger seeds, newly planted sunflower seeds can imbibe more water than other types of vegetable seeds, making them susceptible to rotting in wet soils. Sunflower seeds should be planted into pre-irrigated soil, and only watered when the soil surface is 100% dry, as well as dry 1/4 inch below the surface. Newly germinated sunflower seedlings are also prone to damping off, and should be allowed to dry down between waterings.

Young sunflowers should be provided with fairly regular water, but still prefer a soil dry-down between waterings. After being established, sunflowers are quite drought tolerant. Water deeply, and let soil dry down before watering again. Water progressively more deeply and less frequently to help plants grow deeper roots, which can make them more drought tolerant, and less prone to lodging (falling down) under the weight of heavy heads.

Adequate water is most important just before flowering, during flowering, and during seed production. Sunflowers are sensitive to overly wet soils, and can experience root and stem rot diseases. Drip irrigation is recommended to keep foliage dry and disease free.

GardenZeus Fun Fact: Did you know that the large flower on a sunflower is composed of up to 2000 small individual flowers called “disk flowers?” These flowers form at the precise angle of 137.5 degrees to each other, which produces the maximum possible number of flowers in the space available within the larger flower head. Each disk flower can form a single sunflower seed. The petals around the sides of a sunflower are botanically considered to be another form of flower that doesn’t produce seeds called “ray flowers.”

The brown sunflower disk flowers are in the center and the yellow ray flowers are on the outside.

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Sunflowers in a Sustainable Garden

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