Black Oil Sunflower is an open-pollinated sunflower variety that is primarily used for sunflower seed or sunflower oil production. It can also be very effective when used as a warm-season cover crop. These are really easy to grow on any scale, whether it be a raised bed or a few acres.
When grown as a cover crop, sunflowers work as a soil cleanser and help to remove any soil impurities that might be present. They also have a very deep root system that helps to cycle and scavenge nutrients from the deep. They are also relatively drought-tolerant and perform well in the heat of summer when rainfall may be lower.
Black Oil Sunflower can be direct-seeded or transplanted. Direct-seeding can be easily done with a walk-behind planter like our Hoss Garden Seeder. We recommend using a #3 seed plate and modifying the hole size to fit the variety being planted. Sunflower seed size can vary greatly from one variety to the next, therefore it’s important to always calibrate the seed plate hole size for the variety being planted. Sunflowers grow well when planted on double rows with drip irrigation. Lay one row of drip tape and plant on both sides of the tape to maximize garden space.
When growing as a cover crop, Black Oil Sunflower seed can be broadcast by hand or with a spreader. After spreading seed, it’s a good idea to lightly rake or comb the soil to increase seed to soil contact. This will result in better germination and a better eventual stand of sunflowers. Once all the sunflower blooms have died, you can harvest seeds or simply mow the stalks and incorporate the debris into the soil.
The seeding rate for black oil sunflowers is 20lbs per acre or .5lbs per 1000sq. ft.
Black Oil Sunflower Planting Information
Planting Method: transplant or direct seed
When to Plant: after last frost
Planting Depth: 1/2″
Seed Spacing: 4-6″
Row Spacing: 2-3′
Days to Maturity: 110
Disease Resistance: None
Seeding Rate: 1 lb. per 5,000 square feet