Tall, bright and elegant, sunflowers are a staple plant in many gardens and allotments. Everyone from young children to experienced gardeners enjoy growing these majestic flowers during the summer months. However, what many people don’t realise is that the attraction need not end as the flowers fade.
These tall, graceful flowers add a beautiful pop of bright yellow color to any garden, while also being an incredibly easy flower to care for. Caring for your sunflowers and yielding a good sunflower seed harvest is incredibly easy, and rewarding.
Sunflower seeds are a delicious treat that are incredibly popular around the world. What’s great about this yummy snack is that you don’t have to go out and buy them: you can plant your own sunflowers and harvest the seeds yourself.
As the blooms fade, the central part of the flower produces masses of seed. Some people, myself included, like to leave these in place for birds and wildlife to harvest. But if you are partial to sunflower seeds you can also harvest them yourself.
However, you may find yourself unsure with how to go about starting this. Fear not: we have created this article with the intention of showing you how to harvest sunflower seeds. By following the tips, tricks, and advice provided in this article, you should have a bountiful sunflower seed harvest by the end of the summer season.
If you want to learn how to harvest sunflower seeds, this is the guide for you. Our how to harvest sunflower seeds guide will take you through everything that you need to know.
A popular part of the summer garden, knowing how to harvest sunflower seeds enables you to get even more enjoyment from these colorful plants.
What is a Sunflower?
Before we discuss how to harvest sunflower seeds, I will quickly explain what these plants are. Officially known as Helianthus annuus, these popular plants are members of the Asteraceae family. Other members of the Asteraceae family include daisies and osteospermum.
Sunflowers are native to North America, but have since become a popular flower cultivated around the world. Sunflowers are a beautiful addition to any garden. They produce bright, large, and graceful blooms that shine throughout the summer. Sunflowers are also the perfect flower if you’d like to plant a bee-friendly garden.
Easily identifiable thanks to its large, open flower, the flower’s central disk is actually made up of lots of small inflorescences. These are surrounded by large, usually yellow, petals. You can also find varieties that flower in shades of orange, white, red and deep purple.
Each inflorescence or floret is able to self pollinate, producing one kernel or seed which is contained in the outer hull. Depending on the cultivar the seed can be striped or black.
How to Properly Care for Sunflowers
Here is an example of healthy, happy sunflowers. Notice that the petals are a bright yellow color, and the leaves are a vibrant green. These sunflowers are also placed in a very sunny location, which is perfect conditions for them.
The first step to a good sunflower seed harvest is making sure that your sunflowers have been well taken care of throughout the season. Sunflowers require full sunlight for at least 6-8 hours a day, and should be planted in soil that drains well. Sunflower seeds also grow to be quite large, so you’ll need to dedicate a good amount of your garden space to them.
Sunflower seeds should only be planted once the weather has gotten warm, around mid April to May. Seeds need to be well watered, but once past the germinating phase sunflowers only really need to be watered about once a week (of course, this also is dependent on the amount of rain you get in your area).
It’s also very important to ensure that you only plant sunflower seeds once there is no longer a risk of frost. If you’d like to start your sunflowers outdoors early, there are a few ways in which you can protect them from frost while they germinate.
There are many different varieties of sunflowers for you to choose from. However, if you really want to maximize your sunflower seed harvest, the best choices are larger varieties such as the “Russian Mammoth”.
A large sunflower species can produce up to 2000 seeds, so take this into consideration when deciding how many sunflowers to plant.
Learning how to properly care for sunflowers is the first step towards cultivating a good sunflower seed harvest. Learn how to grow sunflowers to get yourself started.
Protect the seeds from wildlife
An example of sunflowers that have had the seeds picked bare by birds and other wildlife. Based on the color of the stalks, we can also infer that the gardener did not remove the sunflowers in time.
While waiting for the right time to harvest, It’s possible you may run into the problem of birds and other wild animals stealing your seeds. Unwanted animal guests may begin eating the seeds before your sunflowers are ready to harvest.
If you’re worried about this happening, you can cover the sunflowers with a net-like material fabric. You can find various different types of netting available online, such as this one. This also has the added benefit of catching any seeds that fall early.
One way you can discourage birds from eating your sunflower seeds is by providing bird feeders for them instead. You can pick a beautiful bird feeder to add as decor for your backyard, while also keeping the birds at bay.
When to Harvest
Before we discuss how to harvest sunflower seeds, we will first explain when is the best time to start harvesting.
One of the best plants to start from seed, knowing when to begin harvesting is an important part of knowing how to harvest sunflower seeds. Start too early and the seed will be small and disappointing. Wait too long and the visiting wildlife may beat you to it.
Kernels can ripen at any time from July to October. It all depends on where you are growing, which variety you have planted and when the plants were started. In general, the earlier you start your plants, the sooner they are ready for harvest.
As the flowers fade, the petals turn brown and start to shrivel or dry out. Meanwhile, in the center of the flower, kernels start to form.
Continue to pay close attention to the central disk. You will notice the tiny petals drying out. Lightly scraping your hand across them dislodges the petals from the disk. This exposes the tightly packed kernels.
The kernels are ripe and ready for harvest when the calyx, back of the flower head, turns yellow-brown and the outer petals fall from the plant.
As the flower fades, the kernels form.
How to Harvest Sunflower Seeds
If you choose to let the kernels mature on the stalk there is a danger that they will ripen and fall from the plant. Either setting seed where they fall or being spread around the wider area by visiting birds and squirrels. This can result in lots of surprise flowers next year. In fact, did you know that planting some Helianthus annuus is one of the best options for attracting birds to your garden?
If you don’t mind the plants being spread around your garden then allow the heads to dry out on the stalk. If you want to prevent this then you will need to cut the flower head from the plant.
To know when to cut the flower head, watch the back of the flower head, calyx closely. When it turns from its original green to a yellow-brown shade, cut the head along with 6 to 8 inches of stem. You will need to use a sharp knife or pruning shears. Helianthus annuus have notoriously thick stems. These can be difficult to cut through if your tools aren’t sharp enough. A whetstone is a great way to sharpen garden knives and tools.
Cut away any leaves that are still attached to the stem. This removes any pests that may be hiding in the foliage. If you are drying more than one cut stem, tie a few, no more than 4, together with a bit of garden string, such as Jute Twine.
Hang the stems upside down, with the heads facing down to the floor, in a shady or partial sun position that is dry and well ventilated. A shed is ideal. When the heads turn brown you can begin to harvest the seeds.
As the heads dry you may want to place a sheet of paper under the flower heads to catch any kernels that drop. Don’t use a plastic sheet, this can lead to a build up of moisture and may cause kernels to turn mouldy.
How to Harvest Sunflower Seeds by Drying the Heads on the Stem
If you don’t mind some stray seed being spread around the garden, allow the stems to remain in place.
Regularly check the back of the heads. When they turn brown, turn your attention to the kernels. Mature kernels are plump. If one or two have fallen out it means they are ripe and ready to harvest. To prevent wildlife from taking the seed as they mature, try tying a paper bag around the flower head.
When learning how to harvest sunflower seeds you may need to protect the drying kernels from visiting wildlife.
When the seed is ripe, cut the stem about 7 inches from the flower head.
You will notice a protective layer of pollen over the kernels. This protective layer resembles small bits of fluffy debris or green-yellow buds. Its presence helps to protect the seeds as they form.
With a knife or your hand gently scrape away the dry remnants of the inflorescence petals from the center disk to reveal the kernels.
Separating the Kernels from the Flower Head
The next step in learning how to harvest sunflower seeds is to learn how to separate the kernels from the flower head. There are two ways to do this. Whichever method you follow, you will need a bucket or suitable large container to catch the kernels as they fall.
The first method is to simply use your thumbs to rub the kernels away from the flower head. Allow the container to catch them as they fall. To make it easier cut or snap the flower head into smaller, manageable pieces.
Alternatively take two ripe heads or two pieces of the same flower head that are roughly the same size and gently rub them together. Again, do this over the container so that the kernels are caught as they fall. Make sure to remove any extra bits of the stem and petals that may have fallen in with the seeds.
After drying, you need to remove the mature seed from the flower head.
Drying the seeds
Cluster of sunflower seeds laid out. Sunflower seeds are usually easy to remove, and you should garner a large amount of them, such as those pictured here.
Once the seeds have been separated from any other extra plant matter, you can begin the drying process.
First, carefully rinse the seeds out to remove any extra debris. Next, prepare a space to dry the seeds overnight. This can be laid out sheets of newspaper, paper towels, or a towel. Just make sure it is a material that will soak up moisture. To dry the seeds, simply lay them out in a dry, warm area on your chosen material.
Make sure that all the seeds are separated when laid out, as this will ensure that each individual seed dries out properly. Leave the seeds out to dry overnight.
Handling Sunflower Seeds
A vital part of learning how to harvest sunflower seeds is knowing how to handle, prepare and store the seed.
If you want to save some seed for sowing next year, or to feed to the birds, the seed can be stored in an airtight jar, such as a Mason Jar, or an envelope in a cool, dry place until you’re ready to use them. Remember to label and date your envelopes and jars. As it ages a seed loses its viability.
Some people like to eat the seed raw, cracking the shells with their teeth. You can also roast the seed. This makes them easier to crack open. Roasting also gives the seed a richer flavor.
How to Roast
If you are learning how to harvest sunflower seeds so that you can enjoy a homegrown roasted snack, preheat the oven to 400°F. Spread the seed out in a single, flat layer on a baking tray or ungreased roasting pan. Roast for 5 to 8 minutes.
When dry the hulls can be easily cracked open. You may need to return them to the oven for a few more minutes until they are fully dry.
If you prefer salted seeds, add 2 to 4 tablespoons of salt and 1 cup of seed to a quart of boiling water. Simmer for around 15 minutes. Drain the water away and dry the kernels on a baking tray before roasting in the oven as described above.
Finally, if you want to roast the kernels without their shells, you will need to shell each kernel before roasting. This is easier than it sounds. Place half a cup of kernels in a plastic bag and seal it. Lay the bag down so that the kernels are flat.
Use a rolling pin to crack the shells open. After cracking all the hulls, empty the bag into a bowl of water. The broken hulls float to the top, the kernels which are heavier sink to the bottom.
Remove the shells from the water, a slotted spoon is useful here. Drain the water and allow the seed to dry before roasting. Roast the shelled seed for 8 to 10 minutes at 350 °F. Remember to turn them halfway through the process.
You can also check out this video if you’d like some more advice on how to roast sunflower seeds.
The seed is protected by a shell. To enjoy the seed you will need to remove the shell.
You can store raw, unshelled seeds in a cupboard or the pantry for 2 to 3 months. They keep in a fridge or freezer for up to 12 months. Roasted and unshelled, the seed can be stored for 4 to 5 months in a cupboard or up to a year in a fridge or freezer.
One of the easiest flowers to grow, Helianthus annuus are a popular member of the summer garden. Their tall bright blooms bring color and pollinators to the garden. Knowing how to harvest sunflower seeds is beneficial for a number of reasons. It enables you to save seed for sowing next year, feed the visiting garden birds or even keep for yourself as a quick snack.
Jen is a master gardener, interior designer and home improvement expert. She has completed many home improvement, decor and remodeling projects with her family over the past 10 years on their 4,500 sf Victorian house. She is also a passionate farmer who keeps goats, chickens, turkeys cows and pigs on her farm, and an instructor for her community’s Organic and Sustainable Farming project.