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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Plant by June 15 n never
Plant by June 15 n never plant after July second...GoodLuck
I planted sunflowers seeds
I planted sunflowers seeds for the first time in our backyard here in San Diego, CA. Thirty-five of them have come up. They are growing rapidly and beautifully. They all have little heads already. However, they need so much water!! I had no idea. Because of our drought, we are having to water using "gray" water from our rinse water (for dishes), rinse water from bathing, and rinse water from our washing machine. We have no choice about using the gray water, but what I want to know is if we can still eat the seeds having used gray water to grow them? Also, some of the smaller plants do not get enough sun, so I'm thinking of cutting off some of the huge leaves at the bottom of the bigger plants to give the smaller ones more sun. I saw a comment from above that some people have had success with this. Thank you.
Hi Emily, We feel for all
Hi Emily, We feel for all those affected by this devastating drought. We haven't experienced this issue, but here is a helpful fact sheet:
http://www.encinitasca.gov/modules/showdocument.aspx?documentid=1111
"Graywater can be used to irrigate landscaping and plants but not on root crops or edible parts of food crops." At with vegetables, this suggests you'd need to cook the food to ensure no bacteria exists.
To get an accurate answer, we'd need to refer you to the San Diego County Water Authority: www.sdcwa.org/contact-us
This is my first year growing
This is my first year growing sunflowers and something's just not right. They're roughly 2 feet tall now and probably half of them have flopped right over. I can't seem to find anything in regards to this anywhere. Do you have an ideas? The stalks and leaves look fine, they're just not standing. Someone suggested a little boron added to the soil. What do you think?
Lots of sunflower varieties
Lots of sunflower varieties require staking. Give that a try.
I planted sunflowers in early
I planted sunflowers in early May but there is no sign of them yet and it is June 3 could this be because of soil temp I'm in Ireland and it has been cold all through May if I plant some now when should I see growth
It's best to sow sunflower
It's best to sow sunflower seeds directly into the soil after the danger of frost is past. Ideally, when the soil temperature has reached 55 to 60 degrees.
Hello! I recently moved to
Hello! I recently moved to Boise, ID and I'm renting so I do not want to dig up the ground but I want to plant sunflowers ( they're my favorite flower)! I bought mammoth and autumn beauty seeds today and was wondering if anyone could tell me the best way to go about planting the seeds in a pot. Willing to take any suggestions as this is the first time I'm planting them! Also, the temp. gets very hot here in the summer but it is dry air. Any suggestions on watering? Thanks!
You can plant the sunflowers
You can plant the sunflowers in a big deep pot. The taller sunflower varieties also get top heavy and may start leaning. If you grow them in pots you may need to support the stalks against a wall or a fence.
Do not plant mammoth in a
Do not plant mammoth in a pot....plant in ground...goodluck
now I read this... the thing
now I read this... the thing is already flopped over.. I have it braced against a window...
I planted sunflower seeds in
I planted sunflower seeds in mid-april in pot.
Its end of May and the stems have rose about 2 feet already.
Can I keep it in the pot or do I need to move it and plant it on ground. Reading above comments looks like, it needs lot of room for its roots.
Please advise.
Yes, sunflowers need a lot of
Yes, sunflowers need a lot of room for the roots. You can plant the sunflowers in a big deep pot or plant them in the ground. The taller sunflower varieties also get top heavy and may start leaning. If you grow them in pots you may need to support the stalks against a wall or a fence.
About two years ago my wife
About two years ago my wife and I had a sunflower pop up in an area that we had not planted with seed (Birds ?).The flower was most unusual in that it only grew to be about 4 feet tall, but the head was easily 12 inches across. We have tried to find seed to grow these ourselves but have had no luck. Any suggestions as to what variety this might have been we would love to have a yard fullof these.
This is not enough
This is not enough information here to identify the plant but there is a lesson here: If you see a plant you like, try to save some seeds. Or take a picture and bring it to a nursery of cooperative extension for help in identifying it.
Very good information!
Very good information!
We removed an old deck made
We removed an old deck made of treated lumber. NOTHING grew in the soil for neat a year. We figured the cause to be toxins from deck. Now crabgrass, dandelions, and other hardy weeds are growing there. We read that sunflowers are good for taking toxins out of soil, but we hesitate b/c we do not want to poison birds and other wildlife with toxic plants. Is this a legitimate concern?. If yes, we thought we'd remove the flowers at some point, but darn it, we don't want to poison the insects! Any advice would be so appreciated!!
I doubt if the chemicals
I doubt if the chemicals (insecticides, fungicides and preservatives)leached out of the old deck, it's more likely that due to the long period of time the deck was in place the soil beneath simply became "sterile". No sun and little moisture would have caused the death of potential plants (even at microscopic level) and thus probably insect organisms too. The fact the weeds are now growing means that passing birds (and feet) have introduced those seeds there. I would suggest you have a sample of the soil tested, if you don't want to go to that expense, dig in a good layer of compost and even plant a "green fertilizer" and dig it into the soil once it's grown a bit and then plant a hardy groundcover or lawn there.
I thought no I over
I thought no I over fertilized my sunflower. It's wilting. How do I revive it? Please advise. Thank you.
Our big "pest" with the
Our big "pest" with the mature heads are the Titmouse and Jays. So when the seeds start to attract them I cover the heads with large paper sacks with the four corners cut out of the sack. I use a wire tie around the stem to hold the sack in place. This creates ventilation and allows the head to fully ripen.
The other pest are Goldfinches who think the leaves are a great salad. Since the feasting doesn't seem to hurt the plant much we just ignore them and enjoy their presence around the garden.
when planting sunflowers do
when planting sunflowers do you take the seed out of the shell and plant or is it left in the shell
Plant as is. No modifications
Plant as is. No modifications needed.
can I plant a sunflower seed
can I plant a sunflower seed in cotton and in gravel and in dirt what is the best one to plant it in and if you could plant it in it then how?
I've planted them in gravel
I've planted them in gravel before. Just dig below the gravel enough to reach dirt, remove that dirt and replace with soil, put the seed in and replace the gravel. The roots will reach out the dirt underneath the gravel.
Hi, this is my first time
Hi, this is my first time planting sunflowers and I'm trying to figure out when the best planting time would be. I live in western Pennsylvania. The temperature has been jumping from low 50s to high 60s. When do you think the best time to plant them would be? Thanks!
It's best to sow sunflower
It's best to sow sunflower seeds directly into the soil after the danger of spring frost is past. Ideally, the soil temperature has reached 55 to 60 degrees. For western PA, your last spring frost will be around May 6.
I'm planting four 200-foot
I'm planting four 200-foot rows of sunflowers to act as a privacy hedge. As it would cost too much to buy enough netting to protect the sprouts from birds, would reflective scare tape or a few strands of fishing line running above the rows be a good bird deterrent instead?
You can try the mylar tapes
You can try the mylar tapes or tie mylar balloons to sticks. Some people tie aluminum pie plates or old CDs to strings. Your privacy hedge will be stunning when all the sunflowers are in bloom!
I tried that Mylar trick with
I tried that Mylar trick with my apple tree. It didn't work. Good luck.
About 1/2 of our harvested
About 1/2 of our harvested seeds are empty. (no kernels) What are we doing wrong? Southern Missouri.
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