From Seed to Sunflower: How to Grow Your Own Stunning Blooms!
The sunflower plant is a gorgeous flower of summer, with its bright yellow petals and tall, sturdy stems. Growing sunflowers is an easy and rewarding gardening project that anyone can do, regardless of their level of experience.
In this blog post, we’ll provide you with all the information you need to successfully grow sunflowers from seed, including when to plant, where to plant, how to care for your sunflowers, and tips for harvesting your sunflower seeds.
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When to Plant Sunflower Seedlings
Sunflowers are an annual plant that grows best in warm weather. The ideal time to plant sunflower seeds directly in the garden is in the late spring or early summer, once the danger of frost has passed and the soil has warmed up.
Depending on your location and climate, this could be anywhere from April to June. If you live in a cooler climate, you may want to start your sunflower seeds indoors a few weeks before the last frost date and then transplant them outside once the weather has warmed up.
Sunflower seedlings can be planted out after danger of frost but starting them indoors gives everyone a jumpstart on flowering.
Where to Plant Sunflowers
Sunflowers love sunlight, so it’s important to choose a location that receives at least six hours of direct sunlight per day.
They also prefer well-drained soil that is rich in organic matter. Before planting your sunflower seeds, make sure to loosen the soil and mix in some compost or other organic material to improve soil quality.
Sunflowers are fairly tolerant of different soil types, but they do best in slightly acidic to neutral soil with a pH of 6.0 to 7.5. But don’t stress that much about it.
How to Plant Sunflowers
Planting sunflowers from seed is a fairly straightforward process. Here are the steps you need to follow:
- Prepare the soil: As mentioned above, loosen the soil and mix in some compost or other organic material to improve soil quality.
If your soil is well amended already then skip this step.
- Plant the seeds: Sunflower seeds are fairly large and easy to handle. Dig a small hole about 1 inch deep and drop a seed into the hole. Cover the hole with soil and pat it down gently.
If you are plagued by gophers and other critters digging up and eating the sunflower seeds then try to protect them or start them in pots. (I have to start in pots)
- Water the seeds: Water the seeds immediately after planting to help the soil settle around them. After that, water your sunflowers regularly to keep the soil moist but not waterlogged.
- Thin the seedlings: Once your sunflower seedlings have sprouted and are a few inches tall, you may need to thin them out to give them more space to grow.
Multi-branched sunflowers need about 18 inches to 3 feet of space between plants, so if you planted multiple seeds in one hole, you’ll need to remove all but the strongest seedling.
For single-stem sunflowers, you can plant them 6 inches apart.
I choose to plant seeds individually, so there is no need to thin the seedlings. If one fails to germinate I just plant another in a week.
Caring for Sunflowers
Sunflowers are relatively easy to care for, but they do require some attention to ensure they grow strong and healthy. Here are some tips for caring for your sunflowers:
- Water regularly: Sunflowers need regular watering to keep the soil moist but not waterlogged. Water deeply once a week, or more often in hot and dry weather.
- Fertilize: Sunflowers are heavy feeders and benefit from regular fertilization if your soil is lacking. Apply the fertilizer once a month during the growing season. Some will tell you to add a higher phosphorus feed for better flowering but in fact, sunflowers are high nitrogen users.
I prefer feeding my soil to feeding the plants and working on regenerating my soil rather than pouring on fertilizers.
In areas where my soil may be lacking I prefer an organic liquid feed that not only feeds my plants but also boosts my soil. This is the one I am using now.
- Provide support: Depending on the variety, sunflowers can grow quite tall and may need support to prevent them from toppling over. You can use stakes, trellises, or cages to support your sunflowers as they grow.
- Control pests: Sunflowers can be susceptible to aphids, caterpillars, and other pests. Most of the time they don’t do enough damage to worry about but if I see some getting out of control I spray them off with a power spray hose. I also hand-pick them off.
- Deadhead spent flowers: Removing spent flowers can promote more blooms on some sunflower plants, called multi-branching. Many others are single-bloom producers on a single stem.
So make sure what kind you are growing and deadhead the multi-stemmed but plant new seeds of single-stemmed at bi-weekly or weekly intervals.
Renees Garden Seeds has an array of choices with information about each.
Johnnys Seeds also has a wide variety to choose from and they give you information about each one whether it is a single stem or multi. Many cut flower farmers like buying through Johnnys.
Harvesting Sunflower Seeds
One of the best things about growing sunflowers that produce edible seeds is harvesting them. (or you can leave them for the birds to eat during the winter)
Here are some tips for harvesting and storing sunflower seeds:
- Wait for the seeds to mature: Sunflower seeds are ready to harvest when the flower heads have turned brown and the seeds are plump and full.
You can test if the seeds are ready by gently rubbing the seed head with your hand. If the seeds fall out easily, they are ready to harvest.
- Cut the seed head: Use a sharp pair of scissors or a knife to cut the seed head from the stem, leaving a few inches of stem attached.
You can also leave the seed head on the plant to dry and then harvest the seeds later.
- Dry the seeds: Hang the seed heads upside down in a warm, dry place for a few weeks to allow the seeds to dry out completely.
You can also lay the seed heads on a flat surface and cover them with a mesh screen to keep birds and rodents from eating the seeds.
- Remove the seeds: Once the seeds are dry, gently rub the seed head with your hands to remove the seeds. You can also use a fork or a comb to separate the seeds from the seed head.
- Store the seeds: Store the seeds in a cool, dry place in an airtight container. Sunflower seeds can last for up to a year if stored properly.
Frequently Asked Questions (FAQs)
- How long does it take for sunflowers to grow from seed?
Sunflowers usually take around 80 to 120 days to reach maturity, depending on the variety and growing conditions.
- Do sunflowers need a lot of water?
Sunflowers need regular watering to keep the soil moist but not waterlogged. Water deeply once a week, or more often in hot and dry weather.
Of course, this depends upon your local conditions. Do you get summer rain? What about going for long spells when you have no rainfall and have high temperatures? Do what is best in your environment, there is no set formula.
- Can I grow sunflowers in a container?
Yes, you can grow sunflowers in a container as long as the container is at least 12 inches deep and wide. Choose a dwarf or compact variety that will not grow too tall and use a well-draining potting mix.
- How do I prevent birds from eating my sunflower seeds?
Cover the seed heads with a mesh netting or cheesecloth to prevent birds and rodents from eating the seeds.
- Can I save sunflower seeds from year to year?
Yes, you can save sunflower seeds from year to year. Store the seeds in a cool, dry place in an airtight container. Sunflower seeds can last for up to a year if stored properly.
Note: Specialty hybrids do not come true from seed. Meaning you won’t get the same colors the next season. That is because they cross-pollinate and produce a different flower. If growing a particular variety for its color, form, etc rather than seeds for eating you are better off buying fresh seeds annually.
- How tall can sunflowers grow?
Sunflowers can grow anywhere from a foot to over 10 feet tall, depending on the variety. Make sure to choose a variety that is suitable for your growing space.
- Can sunflowers grow in partial shade?
Sunflowers prefer full sun and will not grow well in partial shade. Make sure to choose a location that receives at least six hours of direct sunlight each day.
- Do sunflowers attract bees?
Yes, sunflowers are pollinator-friendly and attract bees, butterflies, and other beneficial insects to the garden.
Some grown for the cutflower market are pollenless so read your seed packet or plant tag for more information regarding it being pollinator friendly.
- How do I know when to harvest sunflower seeds?
Sunflower seeds are ready to harvest when the flower heads have turned brown and the seeds are plump and full. You can test if the seeds are ready by gently rubbing the seed head with your hand. If the seeds fall out easily, they are ready to harvest.
- Can I eat sunflower seeds from my garden?
Yes, you can eat sunflower seeds from your garden. Make sure to harvest the seeds when they are fully mature and dry. You can roast the seeds for a delicious and healthy snack.
If that is your goal grow sunflower varieties that are specifically for eating.
Growing sunflowers from seed is a rewarding and fun gardening activity that anyone can enjoy. With the right growing conditions and care, sunflowers can thrive and produce beautiful blooms and delicious seeds.
Remember to choose a sunny location, prepare the soil, water, and fertilize regularly, provide support, control pests, and harvest the seeds when they are mature. With these tips and tricks, you can grow your own beautiful sunflowers and enjoy the many benefits they provide.