How to Grow and Care for Sunflowers
Written by MasterClass
Last updated: Jun 7, 2021 • 2 min read
Sunflower plants (Helianthus annuus) are more than just large, bright flowers in the garden. Gardeners plant sunflowers to feed pollinators like honeybees, attract birds to ward off garden pests, and to help detox your garden soil.
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7 Tips for Growing Sunflowers
From Teddy Bear to Mammoth, there are many sunflower varieties that you can grow in your garden. Depending on the hardiness zone, sunflower plants can either have short or long growing seasons. After you’ve planted seeds and they’ve started to grow, here are a few steps you can take to ensure that your sunflower plants will flourish:
- 1. Water properly. Sunflower seeds typically begin to sprout 10 to 14 days after planting and require gallons of water per week to continue growing. Water your sunflower plant around the root zone, about three to four inches from the plant. Water the sunflower plant infrequently in order to encourage deep root growth.
- 2. Fertilize sparingly. Sunflowers are heavy feeders that are sensitive to fertilization. Adding nitrogen to the soil can help your plants grow bigger but adding too much can cause sunflower stalks to break, especially when the weather begins to cool, so be careful not to overfertilize. When you do have to use fertilizer, keep it away from the plant’s base.
- 3. Stake your plants. Certain varieties of sunflowers can grow to be over 16 feet tall, so you will need to support the stems. Staking the sunflower’s tall stems will help support the weight of the budding sunflower heads. To stake a giant sunflower, drive upright stakes into the ground and fastening the plant to the stake using plant ties or twine.
- 4. Place in sunlight. Sunflowers need six to eight hours of direct sunlight and long, hot summers to healthily blossom.
- 5. Mulch. Apply three to four inches of mulch to your sunflower plants to keep soil temperatures above 50 degrees, conserve water, and smother weeds.
- 6. Use a barrier. Keep birds, squirrels, and other critters away from your germinating sunflower seeds by covering the planting site with a wide netting. If you live near a deer population, you may want to set up wire fencing to keep them from nibbling on the flower heads.
- 7. Check for pests and diseases. Although sunflowers have few foes, they are susceptible to moth eggs. Check the sunflower blossoms for these pests, and pick them out if you see them. Powdery mildew, downy mildew, and rust are also possible afflictions that may affect sunflowers. Use a safe fungicide to help keep your plants clear of these fungal diseases.
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