With bright blooms that go from mid-summer to early fall, sunflowers say “summer” like no other plant. Our Sunflower Growing Guide covers everything from planting to cutting flowers to harvesting seeds!
Sunflowers (Helianthus annuus) is an annual plant with a large daisy-like flower face. Its scientific name comes from the Greek words helios (“sun”) and anthos (“flower”). The flowers come in many colors (yellow, red, orange, maroon, brown) but they are commonly bright yellow with brown centers that ripen into heavy heads filled with seeds.
Here and yonder, high and low,
Goldenrod and sunflowers glow.
–Robert Kelley Weeks (1840–76)
How Long Do Sunflowers Take to Bloom?
A fairly fast-growing flower, most sunflower varieties mature in only 85 to 95 days. The largest sunflower varieties grow to over 16 feet in height, while smaller varieties have been developed for small spaces and containers and rarely grow larger than a foot tall! The flower heads can can reach over 12 inches in diameter within the large seeded varieties.
Sunflowers are heliotropic, which means that they turn their flowers to follow the movement of the Sun across the sky east to west, and then returns at night to face the east, ready again for the morning sun. Heliotropism happens during the earlier stages before the flower grows heavy with seeds.
Very few plants are as heat-tolerant, resistant to pests, and simply beautiful. Sunflowers make excellent cut flowers and many are attractive to bees and birds.
At the end of the season, it’s easy to harvest sunflower seeds for a tasty snack or for replanting (see instructions below). Learn more about why you should start growing these happy flowers in your garden.
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I think depends on how close
I think depends on how close together they are growing. I think they need to be about 18" apart if you want them that tall. I had my mammoth sunflowers planted about 10" apart and while a few of them are about 7 or 8 feet tall right now, a bunch are blooming at only about 4 to 5 feet tall.
I wanted to know that I m
I wanted to know that I m planning to plant sunflower in my farms where I grow cotton as well as soybean. Is it possible for me to grow both the plants at the same time and harm none
Sure, you can plant
Sure, you can plant sunflowers next to your soybeans and cotton. They are traditionally good companion plants as long as you plant the sunflowers in separate rows.
I planted a mammoth seed in a
I planted a mammoth seed in a pot a few weeks ago and the stem cannot hold itself upright...
It's about 5 inches tall now and I have it leaned against the window...
Large sunflowers often need
Large sunflowers often need to be staked.
is there a way to post a
is there a way to post a picture?
You can post a picure in our
You can post a picure in our picture gallery here: www.almanac.com/photos/gallery
If you have a question for us, you can always post here and add the link to your picture.
You need to move the mammoth
You need to move the mammoth sunflower from the pot into the ground. They have the need for roots to expand. If you don't move it, it will not do well. It may even blow over in a wind or die before the plant can flower if left in the pot. Move to the ground. Once you move it because it's already leaning you may need to support it against something (tie it to a fence, etc). They need food so fertilize and don't fertilize directly onto the plant; fertilize about 10-18" out from it in a groove made around the plant. Birds, bees, squirrels love it. In case you see the flower drooping after it blooms and looks so lovely it could be caused by them feeding on it. It's a labor of love but worth the big beautiful flower you get.
I planted the same type of
I planted the same type of seeds this year as last year, but I planted more seeds, and spaced them about 9 inches apart from each other (this was in late May in Beijing). Now the plants are at least 10 feet tall, but the blossoms are small, about 3 inches in diameter (this is the center part where the seeds are). Last year they were at least 7 inches across (where the seeds are). Are the blossoms small because I planted the seeds too close to each other?
My 7 year old planted 2 dwarf
My 7 year old planted 2 dwarf sunflowers from seed and gave them to me for mother's day this year. I replanted them into somewhat bigger pots than what they had come in.
One sunflower bloomed about 10 days ago. It was just magnificent!! We just came back from a 4 day trip up north to find the 1 sunflower that had bloomed so magnificently, dying, drooping, and it's seeds falling out. My neighbor said she had been watering it. We live in Minnesota and it's been in the 90's lately.
What can I do to revive my poor sunflower?
Is your sunflower in a very
Is your sunflower in a very deep pot? Sunflowers need room for their roots so when grown in a pot, it has to be a deep one. And sunflowers are heavy feeders so adding a slow release granular fertilizer to the soil will benefit the plant.
Hi I have 3-4ft sunflowers in
Hi I have 3-4ft sunflowers in pots not quite flowered can I put them in the ground as I have had a change of mind regards rob
Hi, can the same sunflower
Hi, can the same sunflower seeds used for growing be eaten? must it be processed or are they typically the same?
It is not advised to eat the
It is not advised to eat the seeds in the garden seed packets.
Can anything be done with the
Can anything be done with the stalks?Is there anything useful that the stalks can do>?
I planted sunflowers about
I planted sunflowers about two weeks ago, at first they were beauties seemed to be doing fine, then all of a sudden lost their leaves, dying. What did I do? They seem to get enough sun. I water about every other day. Temps in the 80s. Help. Same thing always happens. All my other flowers are beautiful.
Make sure your sunflowers are
Make sure your sunflowers are getting a lot of sun -- like at least 6 hours' worth a day. They also need to be moist, but in well-drained soil. Water them deeply (to encourage root growth), but not too often. And the soil needs to be fertile -- well-rotted compost mixed in works well.
Hello, here in the Republic
Hello, here in the Republic of Panama the sunflowers grows by itsetf under and around my parrot cage. Therefore, I would like to start my own plantation. What is best time of the year to plant the seeds.
I welcome and appreciate any advise.
Best regards
I want to plant sun flowers
I want to plant sun flowers this week June 23 for dove hunting. Do you think the seeds will be ready for doves to eat by September? I live in Peoria Illinois
I am planting my field
I am planting my field tonight. Last year I planted the third week of May, and they started to flower in early to mid August. I don't think the seeds would be ready by Sep 1st, but there should be flowers out by then. It seemed to me last year that the doves were in my field as soon as the sunflowers were tall enough and strong enough to hold the birds, which was a few weeks before the heads opened up anyway. I would say the least you can do is try!
We've been growing many
We've been growing many varieties from seeds past 2 years. This year we have lots that popped up before we planted our started seeds, assuming from fallen seeds last year, will they flower?
Yes, sunflowers will
Yes, sunflowers will self-seed and reproduce to produce flowers.
I planted a sunflower in a
I planted a sunflower in a planter box back in early May (maybe late April). It is about 6 feet tall now, with a healthy and hearty stalk, and it has been green and healthy until last week. Suddenly the leaves are all wilting and turning brown. Is it because I water too much (lightly 3 days a week)? Is it because I have it in a planter box and it isn't getting enough root space (the box is only about a foot deep)? Is it too late to try to save it? Any help would be so appreciated. I've been really enjoying watching my sunflower grow and I'm devastated it seems to be dying.
Hi, I have already planted my
Hi, I have already planted my sunflower seeds for 3 weeks already. It did germinates. But it's been 3 week but just like a inch tall? it only have 1 pair of leaves and that's all. What happened?
Hi, There are numerous
Hi,
There are numerous factors that may have affected the size and health of your plants. Unfortunately it is difficult to evaluate and narrow down precisely what happened.
Based on my experience however, small sunflowers may be associated with overcrowding, nutrerint deficiencies in the soil, unfavorable weather conditions, not enough sunlight, disease, transplant shock, drought/overwatering stress, or insect/ fungal damage either above ground or below.
I would continue to wait and allow the plants more time to grow. If they continue to perform poorly.. Let them grow the entire season until they die to see what happens.
Also, check to see how closely your sunflowers are growing, if they are crammed together tightly, air cannot circulate between the plants and they will also compete and ultimately grow weak and stunted.
Any of the above mentioned factors may be responsible for your small sunflowers.
If you would like to precisely identify the cause of your small plants..you can take soil and plant samples and send them to a lab for evaluation..they will identify what went wrong or what is missing from your soil..you can then correct accordingly and gain experience for the future.
I am confused by the
I am confused by the following instructions:
"Find a well-drained location, and prepare your soil by digging an area of about 2-3 feet in circumference to a depth of about 2 feet."
and
"Give plants plenty of room, especially for low-growing varieties that will branch out. Make rows about 30 inches apart. (For very small varieties, plant closer together.)
Plant the large seeds no more than 1 inch deep about 6 inches apart after it has thoroughly warmed, from mid-April to late May."
Should I plant the seeds in the trench described in the first instruction by following the guidelines in the second instruction?
Hi Liz, Just turn the soil
Hi Liz,
Just turn the soil over in a section of your garden and follow the instructions on how deep and how far apart to plant.
I gathered some sunflower
I gathered some sunflower seeds from a dried seed head that I found on the road near a field of sunflowers in Tuscany last Fall. Not sure what variety it is. Is it too late to plant in Seattle, WA area? I had misplaced the envelope with the seeds in it and just found it today (June 14th). Any idea what variety it might be? Tiny black seeds. It seemed that all of the sunflowers in Tuscany were the same variety. Thanks!
Hi, The seeds you collected
Hi,
The seeds you collected are likely from a "wild" uncultivated strain of Helianthus annuus. Wild H. annuus differs from traditionally cultivated varieties because wild forms typically have numerous branching stems and smaller flowers. Also, they have different germination habits than domesticated forms.
If you would like to plant the seeds you collected.. I would highly suggest that you sow them in the fall or winter because they likely require stratification(meaning to be exposed to cold, snow, and frost) for improved germination. If the seeds are stratified, a naturally occurring chemical called auxin will be broken down, thereby allowing increased germination rates in the spring.
Naturally occurring chemical inhibitors such as auxin are found in most wildflower species. The chemicals are necessary so that germination does not occur until ideal conditions are present in the spring.
Consider this, If the seeds were dispersed and then germinated in the fall after the plant has finished its life cycle..the newly emrged sprouts will be killed by the harsh, cold weather. However, chemicals in the seeds protect this from happening by delaying germination until spring.
Ultimately, to answer your question...if you planted the seeds now, they would probably germinate, but very sparsely and you would get poor rates..likely about 5-20%. Whereas, if you sow the seeds in the fall..they will sprout in the following spring and germination rates will be relatively 50%+..that figure will be higher depending on the quality of the seeds.
Finally..in contrast, why do cultivated, domesticate sunflower varieties not require stratification? This is because domesticated varieties were bred to possess specific desirable traits..and in this case..humans eliminated the need for stratification to make the process of planting sunflowers more effective and streamlined.
Take my advice for planting wild sunflowres. I have gained my knowledge through experience and years of trial and error. I have tried many planting techniques with native, wild sunflowres and now through experience; I know the best methods.
I just want to double check
I just want to double check if it's too late to plant sunflowers at this time of the year. I know you said to plant between mid April to end of May, but what if I start planting them end of June? Or some time during summer?
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