Here's what you need to know about this popular bird seed, from which birds like to eat it to how to grow your own.
Sunflower seeds are a staple in the diets of both people and backyard birds around the world. But while humans prefer the striped variety, have you ever wondered why so many bags of black oil sunflower seeds fill the aisles at your local home improvement store?
“Sunflower seeds are one of the more popular seeds to feed birds, whether alone or in blends,” says Brian Cunningham, Chief Naturalist for Wild Birds Unlimited. They are popular because they attract so many different kinds of birds, but the one birds — and those of us who love to feed birds — prefer most are black oil sunflower seeds.
Here’s why black sunflower seeds are a favorite among animals and people alike, plus bird feeding tips and advice on how to store sunflower seeds so they stay fresh as long as possible.
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What Are Black Oil Sunflower Seeds?
Black oil sunflower seeds come from a cultivar (or modified version) of the sunflower plant Helianthus annuus. They’re an annual crop, used primarily for making cooking oil and as wild bird food.
Black oil sunflower seeds are popular for bird feeders because of their high oil content, which is beneficial for nutrition and calories. Also, their thin shells are easier for birds to crack open than other types of sunflower seeds. Humans generally don’t eat black oil sunflower seeds because the hulls are small and more difficult to shell.
What Birds Eat Black Oil Sunflower Seeds?
In general, most seed-eating birds are attracted to black oil sunflower seeds. These include:
- Finches (house, purple, gold, rosy, Cassin’s)
- Chickadees
- Nuthatches
- Northern cardinals
- Mourning doves
- Tufted titmice
- Towhees
- Blackbirds
- Woodpeckers
- Evening grosbeaks
- Redpolls
- Pine siskins
- Indigo buntings
- Gray catbirds
- Bushtits
- Grackles (house and common)
- Black-billed magpies
- Sparrows
- Jays
What Feeders Work Best for Black Oil Sunflower Seeds?
Hopper, tube, and tray feeders all work well for black oil sunflower seeds, as long as their holes are large enough for the birds to extract the seed.
How To Grow Black Oil Sunflower Seeds
Growing sunflowers is easy throughout most of North America, except places with short summers (they die at the first frost) or lots of humidity.
“People should grow sunflowers,” says Pam Perry, a certified Cooperative Extension Master Gardener. “They are fun, they’re universal, they’re native to the New World, so they’re ours, and they are welcome in a garden anywhere in the country.
“They’re great for attracting beneficial insects and pollinators. They’re pretty. And the neighbors think it’s really cool when your front yard sunflower is going wild.”
Steps for growing sunflowers:
- Buy seeds at the local garden center or nursery. If you want to plant more than just black oil, get ones known for producing an abundance of seeds. “If gardeners are meticulous about maintaining organic integrity in their gardens, they should certainly look for organic sources,” says Randel Agrella, senior horticulturalist with Baker Creek Heirloom Seed Company. “If they’re less concerned, they can probably just plant seed that they obtained as bird feed. That’s assuming the seeds haven’t been treated in some way, like by exposure to heat, to lessen their ability to sprout.”
- Plant them in the spring, after the last frost, in a sunny location. Remember, they get big, so don’t put them where they’ll crowd out smaller plants. “[In most of the country] they will mature with little effort or care,” says Agrella. “Soil for sunflowers needn’t be especially rich. Average garden soil suits them well.”
- Water them as needed — once a day for the first week or two, then once a week thereafter. “They do grow best with ample moisture, but once established they can tolerate considerable heat and drought,” says Agrella.
- Harvest in 90 days. They flower in 60 or so days, but they’ll be ready to harvest in 90 days, when their heads turn down and the inner flowers shrivel.
Steps for harvesting sunflower seeds:
- When they start to wilt, cover the heads you want to save with a fine mesh like mosquito netting, or even just a paper bag stapled to keep it from blowing off. “Most of the time birds will come by and pick them clean,” says Philip Kauth, Executive Director at REAP Food Group and former director of preservation for Seed Savers Exchange. “That’s the challenge. If you want to reseed your own sunflower seeds, you have to protect a couple of the heads.”
- Or, cut off the flower heads and bring them inside to dry. You’ll know they’re dry because the seeds will be easy to separate from the heads. “A lot of times they will actually fall out when they’re dry enough,” says Kauth. “Other times you have to kind of rough them up with your finger and they’ll fall out.”
- Alternatively, you can store the heads with the seeds intact. Then when you’re ready to use them, just place them on platform feeders for the birds.
- Store seeds in a cool, dry place to prevent mold or keep them from going rancid.
- Leave the stalks standing if you can for winter perches and foraging. If they have to come out, compost them. “They’re really good at drawing nutrients out of soils, so we recycle them back into the soil through compost,” says Perry.
Although sunflowers are annuals, once you establish a sunflower patch, it’s simple to keep going year after year. “Most sunflowers will seed themselves,” Kauth says. “They’ll just drop to the ground and hang out over winter.”
How Should I Store Black Sunflower Seeds?
Because black oil sunflower seed has a high oil content, eventually it will go sour or stale and become unappealing to birds. To prevent this, they should be stored in a cool, dry place. The more heat and humidity in your area, the shorter it will stay fresh.
“Under normal storage and use conditions, seed will stay fresh and healthy for birds until it is completely consumed,” Cunningham says. “However, unusually wet or humid weather conditions, or periods of slow bird activity can potentially cause bird seed to deteriorate or spoil.”
Cunningham offers the following tips for storing and preserving your sunflower seeds:
- Always store your bird seed in a cool, dry location outside your home.
- Store bird seed in rodent and insect-proof containers.
- Never mix old seed with new.
- During warm weather, store only the amount of seed that your birds can consume over a two-week period.
- During cooler and winter weather, expand that storage to four weeks.
- Keep a one or two-day supply of seed in your feeders to ensure it is eaten quickly and stays fresh.
- Discard moldy, rancid or foul-smelling seed, which can be a health hazard to birds.
FAQ
Are black sunflower seeds safe for all animals?
Black sunflower seeds are safe for all backyard animals to eat, including birds, squirrels, raccoons, opossums, and rodents, as well as farm animals like horses, chickens, goats, and even rabbits. Black sunflower seeds are also considered non-toxic for dogs and cats. The only animals that should not consume black sunflower seeds are alpacas and llamas, according to the Journal of American Veterinary Medical Association.
Can humans eat black sunflower seeds?
Yes! Black oil sunflower seeds are safe for human consumption in any capacity, but you’ll most often spot them as an ingredient in common cooking oils since they are trickier to crack open as a snack.
About the Experts
- Brian Cunningham is the Chief Naturalist for Wild Birds Unlimited where he has served in a variety of capacities for over 20 years. Brian holds a bachelor of science degree in Forest Recreation from Purdue University.
- Pam Perry is a certified Cooperative Extension Master Gardener and has served as Curator and Master Gardener for the Maricopa County Cooperative Extension at the University of Arizona. She grew up gardening in Vermont, and is a graduate of the College of Agriculture and Life Sciences at the University of Vermont.
- Randel A. Agrella is a Senior Horticulturist with Baker Creek Heirloom Seed Company, a retailer specializing in selling sustainable, heirloom seeds, where he has overseen rare seed production since 2005.
- Philip Kauth is the Executive Director at REAP Food Group after previously serving as Director of Preservation for the Iowa-based Seed Savers Exchange for eight years. He holds a doctorate degree in Horticultural Sciences from the University of Florida.
