Growing Sunflower

helianthus annuus : Asteraceae / the daisy family

Jan F M A M J J A S O N Dec
      P P              

(Best months for growing Sunflower in USA - Zone 7a regions)

  • P = Sow seed
  • Sow in garden. Sow seed at a depth approximately three times the diameter of the seed. Best planted at soil temperatures between 10°C and 30°C. (Show °F/in)
  • Space plants: 20 - 45 cm apart
  • Harvest in 10-11 weeks.
  • Compatible with (can grow beside): Cucumbers, Melons, Sweetcorn, Squash
  • Avoid growing close to: Potatoes

Your comments and tips

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14 Apr 22, Marjorie (USA - Zone 9b climate)
I’m planting mammoth sunflower in zone 9b (FL). I started the seeds in containers and moved them to the ground. For some flowers, I dug holes and filled with garden soil. For others, I planted in the ground, which is sandy. Those seem to be doing okay, too. They get sun from sunrise to sundown. Would you plant them in sandy soil?
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19 Apr 22, (USA - Zone 5a climate)
Sandy soils just require more watering and fertilising.
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23 Jun 22, Cristal Chacon (USA - Zone 8b climate)
I planted sunflower seeds today. Hoping to get blooms by mid August. Do you think this will happen? Or not enough time?
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13 Aug 22, Theresa C. Dougherty (USA - Zone 7b climate)
Can I plant sunflower seeds in mid August to get fall sunflowers .? I live in zone 7 b ,I grow them first in side and plant outside .
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21 Aug 22, Jennifer Bozick (USA - Zone 6a climate)
When is a good date to start planting Sunflowers in Kansas 6a growing zone?
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04 Sep 22, (USA - Zone 6a climate)
In the Planting Guide it says APRIL MAY.
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21 Feb 23, Jordan (USA - Zone 5b climate)
Hi! We are looking to plant sunflowers from seeds in the North Shore of Chicago area, I believe we are zone 5b for zip code 60045. I have seen people reference "the guide" but am curious if someone could point me towards where I might find this magical panacea of information? Thank you! (Gardenate uses https://www.gardenate.com/zones/#zone-US)
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22 Feb 23, Anonymous (Australia - sub-tropical climate)
You work out your climate zone from the blue tab at the top of the page. Then go to the plant you want to grow - sun flowers.
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20 May 23, David (USA - Zone 4b climate)
Am in zone 4b. Is there a Sunflower I can plant that only gets 2 feet tall?
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06 Jul 23, Brayden (USA - Zone 8b climate)
Botanical Interests has some good dwarf varieties like Sunspot Dwarf that grows 18-24" tall and is good for container planting
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When is the last month I can successfully plant Mammoth Sunflower seeds in my zone 8b?

- Susie

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This planting guide is a general reference intended for home gardeners. We recommend that you take into account your local conditions in making planting decisions. Gardenate is not a farming or commercial advisory service. For specific advice, please contact your local plant suppliers, gardening groups, or agricultural department. The information on this site is presented in good faith, but we take no responsibility as to the accuracy of the information provided.
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