How to grow sunflowers

Sunflowers 101

Planting Sunflowers

• Sunflowers are sun worshipers that grow best in spots that get six to eight hours of direct sun per day.
• They have long tap roots that need to go several feet into the ground, so sunflower plants prefer loose, well-drained, somewhat alkaline soil with a pH of 6.0 to 7.5.
• Sunflowers are heavy feeders, so they’ll be healthiest and generate the most blooms in nutrient-rich soil that has had compost or other organic matter mixed into it.
• Growing sunflowers in pots is possible if you choose a smaller variety, like “Short Stuff” or “Teddy Bear.” Be sure the pot is deep enough to accommodate their tap root.
• If you’re growing one of the giant varieties that top 10 feet in height, plant them in a sheltered location or along a fence so they’re protected from the wind. Otherwise, a gust of wind could tip them over.

• Plant seeds after the danger of spring frost has passed and the soil temperature is at least 60 degrees. This will be between March and May, depending on where you live.
• Plant the seeds no more than an inch deep and about 6 inches apart. Thin the seedlings once they hit 6 inches tall, leaving the strongest plants about 12 inches apart.
• For continuous blooms, stagger your planting, sowing a new row of seeds every two to three weeks, beginning in the spring. Succession planting, as this is called, will keep you supplied with continuous blooms until first frost.
• How long does it take for sunflowers to grow? From the time you put the seed in the soil to bloom ranges between 80 and 120 days, depending on the variety.

Caring for Sunflowers

• When the plant is small, water the area around the roots, about 4 inches from the plants.
• Once the plant is established, water deeply but infrequently to encourage the plant to grow deep roots. Water once a week with several gallons of water per plant, more often if the weather is very dry or very hot.
• Tall varieties may need support so they don’t topple under the weight of their blooms. Bamboo or other types of wood stakes work well.

Pests and Diseases

Cutting Sunflowers for Bouquets

• Cut flowers early in the morning, before heat has stressed the plants. Harvesting blooms in the middle of a hot day can cause the flowers to wilt prematurely.
• For sunflower varieties that branch into multiple stems, cutting the main stem of the plant before its bud has opened will encourage the plant to make more blooms on the sides of the stem. More flowers is good.
• Handle cut flowers gently so their petals don’t fall off. Cut sunflowers will last about a week in water at room temperature.

Harvesting Sunflower Seeds

• Let the flower dry on or off the stem until the back of the head turns brown and the seeds are plump.
• To keep birds and squirrels from getting the seed, you’ll need to cover the flower heads with garden fleece, cheesecloth or a paper bag after the seed heads mature and the petals fall off the blooms.
• Cut the head off the plant leaving about 6 inches of stem. Place the head in a container to catch loose seeds.
• To remove the seeds, brush your hand over the seed head, knocking out the seeds.
• If you’re saving the seeds to plant, store them in an airtight container in a cool, dry place until planting time.

Recommended Varieties

Garden Design Suggestions

• Some varieties of sunflowers can get very tall and shade other plants, so don’t plant sun-loving companion plants too close.
• Tall varieties of sunflowers work best as a screen, at the back of a border bed, or along a fence.
• Shorter varieties can be grown in the middle of a border or in pots.