Robin Trott, UMN Extension Educatorflowers were ideal in mixed fall bouquets, and bloomed prolifically until frost.
Keep in mind these cultural practices once you have selected your perfect sunflower variety.
- Select a site that receives at least 6 hours of sun a day. (More is preferable)
- Sunflowers prefer loose, well-drained, rich soil; so amend with compost if you have heavy clay or sandy soil.
- Sow seeds directly into the garden once the soil has reached 50°. (Cooler than this will slow development.)
- Plants seeds at a depth 2 times their width, and space close (6") to promote tall plants; and small, bouquet sized heads. This close spacing will soon shade out weed competition and mature plants will protect and support each other.
- Sunflowers are heavy feeders, and should be fertilized. Side dress with a balanced fertilizer (10-10-10) every 21 days during the growing season.
- Keep your sunflowers weed free. Weed competition reduces the quality of your sunflowers.
- Tall sunflower varieties will need support to protect them from wind damage. Stake them or grow them through horizontal support netting to ensure your plants remain standing after our typical summer "hazardous" weather.
Harvest your sunflowers during the coolest part of the day. The plants should be free of dew and moisture. Cut when petals begin to lift off the face, but are not completely open. Make sure your cutting tools and containers have been sterilized with a 5% bleach solution. Cut stems at least 24" long and at an angle for best results. Sunflowers prefer clean water to floral preservative. (Floral preservative can actually over-hydrate your flowers, making them wilt.) Place your cut sunflowers in a cool place as soon as possible after cutting. If wilting occurs, don't worry, leave them in water for 24 hours, and they should perk right up. Vase life for fresh cut sunflowers is 7 to 10 days, with pollen-less flowers having the longest vase lives.
Sunflowers are a colorful choice for your garden, make long lasting cut flowers, and provide food and habitat for wildlife. It's not too late to start them for this gardening season. Select your cheerful sunflower variety today, and get growing!
Until Next Time, Happy Gardening!
Bring me then the plant that points to those bright Lucidites swirling up from the earth, And life itself exhaling that central breath! Bring me the sunflower crazed with the love of light.
~ Eugenio Montale