How to grow Sunflower

Helianthus annuus

Protect your sunflowers from moths slugs and birds by covering the heads with plastic netting. Needs water to get established, but can tolerate mild drought after established.1

Growing Sunflower from seed

Sow one seed per pot using a 10cm / 4 inch size plant pot and place in an airing cupboard for a couple of days until the seedling pushes through.
Alternatively, germinate in a cold frame or on a windowsill and grow on in bright conditions under glass.
Try not to let the seedling grow too tall before it is planted out, this is prevented by coo bright conditions

Try to aim for a seed spacing of at least 9.75 inches (25.0 cm) and sow at a depth of around 0.49 inches (1.25 cm). Soil temperature should be kept higher than 13°C / 55°F to ensure good germination.

By our calculations*, you should look at sowing Sunflower about 21 days before your last frost date .

Transplanting Sunflower

Condition the seedling to cooler outside conditions gradually. Plant outside as soon as danger of a hard frost is past, as the young plant will quickly grow a taproot. Seedlings will tolerate temperatures down to 29 F (-1 C). Young seedlings need protection from slugs.
Choose a bright, sunny spot out of the wind

Ensure that temperatures are mild (minimum night temperatures should be around 10°C / 50°F) and all chance of frost has passed before planting out, as Sunflower is a half hardy plant.

Harvesting Sunflower

Flowers can be cut for the house. If left to mature on the plant, the seeds help the birds through the winter. Alternatively the sees can be harvested after the flower has ended. Cut the head on a dry day and place in a paper bag to continue to dry off. The seeds will easily drop out of the flower head when they are ripe

Seed Saving Sunflower

Covering the seed head with netting, floating row cover, or a paper bag can help keep the birds off the seeds while they ripen on the plant. As soon as you see birds going for the seeds they are likely ready to be harvested.

Seed viability is five years.

How long does Sunflower take to grow?

These estimates for how long Sunflower takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.

Days to Germination How long does it take Sunflower to germinate?
8 days

Average 8 days | Min 1 days | Max 22 days (594)

Days to Transplant How long until I can plant out Sunflower?
+ 22 days

Average 22 days | Min 1 days | Max 57 days (141)

Days to Maturity How long until Sunflower is ready for harvest / bloom?
+ 63 days

Average 63 days | Min 23 days | Max 209 days (12)

Total Growing Days How long does it take to grow Sunflower?
= 93 days

When should I plant Sunflower?

Our when to plant Sunflower estimates are relative to your last frost date.

When to sow The number of days to sow Sunflower before or after your last frost date.
21 days before Last Frost Date

Sunflower Etymology

The sunflower gets its name from the Greek word “Helios” (meaning sun) and “anthos” (meaning flower)
The botanical epithet is from the Latin angustifolius meaning “annual”.2
The botanical epithet is from the Latin helianthus meaning “sun-flower”

Sunflower Folklore & Trivia

Used medicinally throughout the ages for wart removal, snake bite and sunstroke treatment.
The Aztecs worshipped sunflowers – they placed sunflower images made of gold in their temples.
Is associated with the zodiac sign Leo (23 July to 22 August) because of their mutual relationship with the Sun.
The Navajo made a tea with the leaves as a treatment for feverish pregnant women.
Sunflower oil was also utilised as a skin wash.

Other names for Sunflower

Tournesol, Girasol, Sonnenblume, Slonecznik, Blodyn haul, Zonnebloem, Duwwar al shams, Suncokret, Sunflower

Helianthus annuus L.

Misspellings: Helianthus annus

Footnotes

1 Missouri Botanical Garden

2 Latin Dictionary


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