How To Grow Sunflowers

Sunflowers are like a big burst of happiness on a stalk. You can’t help but smile when you see a sunflower and children squeal with joy at the sight of those vibrant bright yellow petals.

The sunflower is easy to identify because there is no other flower like it on earth. The plants range in size from a small 1-footer that can be grown in a pot to a towering 15-footer that produces flower heads that are larger than a dinner plate.

The seeds are edible, the sunflower stalks are sturdy and usable, the plants are easy to grow, and it’s fun to watch the flower heads move and follow the sun throughout the day. Use these tips for planting and growing sunflowers so you can enjoy everything that these hardworking, beautiful flowers have to offer.

Sunny Location

As you may have already guessed, these beauties need to be grown in a sunny location. A location that provides them with at least 6-hours of direct sun each day is essential. A location that will place them in full sun all day is ideal.

When To Plant Sunflowers

Sunflowers are annuals and should be planted in early spring after all danger of frost has passed. Although the stalks grow rapidly, it will take the plant 70-100 days to reach maturity. 

Soil Preparation

Due to the rapid growth and large plant size, sunflowers are heavy feeders and drinkers. They need nutrient-rich soil to grow in and soil that drains well. Soil that is rich in organic matter will provide the plants with nutrition and moisture for their summer lifecycle.

Prepare the soil by incorporating plenty of compost into it. Create a 50-50 mixture of potting soil and compost for sunflowers that will be grown in a container and incorporate 2-4 inches of compost into outdoor soil before planting seeds.

Seed Planting

Plant seeds 1/2-inch deep into prepared soil and cover lightly with soil. Space the seeds 6-inches apart. After the plants are 6-inches tall, thin them out to 12-inches apart.

If growing in a container, plant one seed of a tall-growing variety in the center of a 12-inch container. If the seeds are for a smaller variety of sunflower, 3 seeds can be planted around the perimeter of a 12-inch container.

Water

When the seeds have been planted in soil that has been amended with compost, the plants will not need any more food during their growth cycle. They will, however, need lots of water.

Sunflowers develop a long taproot that helps keep the tall, top-heavy plant anchored in the soil. Regular deep watering will help the taproot grow deep and promote the growth of feeder roots which develop laterally and remain just below the soil surface.

Apply a gallon of water per plant, 4-inches away from the base of the stalk weekly during times of drought or any time the sunflower head and leaves appear wilted.

Flower Harvest Time

Harvest the flowers in the morning before the sun shines on the plants to prevent plant stress. When harvesting blooms from varieties that produce more than one flower head, cut the flower on the main stalk first to encourage the other flowers to continue maturing.

Seed Harvest Time

Sunflower seeds are edible and make a tasty, protein-rich snack. The seeds also are a favorite food of chickens and provide healthy nutrition for backyard poultry.

To harvest the seeds, allow the flower heads to remain on the stalks until all the petals have fallen off and the seeds plump up and turn black. Cut flowerhead off of the stalk, turn upside down, and shake seeds into a large container.

To prevent birds from eating all the seeds while they are ripening, place netting, cheesecloth, or a paper bag over the flower heads.