Sunflower
Helianthus annuus
Botanical family: Asteraceae
Helianthus annuus, native to North America (domesticated by the first peoples 4000-5000 years ago). Varieties with edible seeds (Jumbo, Mongol Giant), oil types (industrial varieties), cut-flower types (Sunbright). Flowering July-September. Harvest of the seeds September-October when the flower bends over and browns. Source: Macías F. A., Molinillo J. M. G., Varela R. M., Galindo J. C. G. (2007), Allelopathy, a natural alternative for weed control, Pest Management Science 63(4):327-348, DOI 10.1002/ps.1342.
Full sun
Rich
Moderate: its taproot helps it cope with drought; watering around flowering improves the crop
Frost-sensitive annual: its seedlings withstand light frosts, less and less as they grow
An annual killed by frost in your zone
Bees carry pollen from plant to plant; many hybrids also set seed alone, older varieties do not
Better crops with several plants or two varieties
Role in permaculture
A tall plant (1.5-3 m), a major nectar plant of late summer, a living support for the climbing bean (a variant of the Three Sisters). Its seeds feed the birds in autumn, accept this sharing.
Good companions
Fix nitrogen from the air (legumes)
Traditional companion planting (benefit not demonstrated)
Poor companions
Allelopathy, reputed or observed: may slow some neighbours
Insects attracted or useful
Seasons & availability
Sown in April and May, under cover in pots or outdoors once the frosts are past, the sunflower blooms all summer and gives its seed in September and October; dried, the seed keeps for the rest of the year.
Available: January, February, March, April, May, June, July, August, September, October, November, December.
Guidance for the oceanic / temperate climate; it may vary with your region, altitude, exposure and growing method.
Sources
- GNIS (Semencemag), « Tournesol, techniques de culture et activités pédagogiques » (semencemag.fr/images/fiches_bo/cultiver-jardiner-tournesol.pdf)
- La Ferme de Sainte Marthe, « Réussir la culture du tournesol » (fermedesaintemarthe.com/en/blogs/comment-reussir-la-culture-de/reussir-la-culture-du-tournesol)
- Plants For A Future, « Helianthus annuus » (pfaf.org/user/Plant.aspx?LatinName=Helianthus+annuus)
Nutritional & medicinal properties
For educational purposes. Not a substitute for medical advice. Effects depend on the form, the dose and personal context.
Precautions & contraindications
Only eat food-grade seeds: those sold for ornament, for birds, or harvested from garden varieties may have been sprayed and are not suitable for food. Allergies to sunflower seeds exist, particularly in people sensitive to Asteraceae (possible cross-reactions). Commercial seeds are often salted, to be taken into account. Keep dry to avoid rancidity of the fats.
Family behaviour: Asteraceae
In general, Asteraceae are a family rich in flowers appreciated by pollinators and beneficials (pot marigold, yarrow, chamomile). It is very scattered, from the mildest lettuce to the allelopathic sunflower.
But this plant is an exception
Its allelopathic compounds have mainly been studied to suppress weeds: in the laboratory and in pots, its extracts reduced the growth of young wheat (Anjum and Bajwa, 2010). An effect on potato and other garden vegetables is not established; as a precaution, do not dig its residues in just before sowing. A traditional stake for climbing beans, and very nectar-rich.
Understanding families means learning one rule per family rather than every pairing one by one. Learn more →
Species & varieties
The best-known species and varieties in France.
Common varieties
Voices of peoples
Paraphrases attributed to their documented sources. Never an invented quote.
Hidatsa (Hidatsa Nation, village of Like-a-Fishhook, Missouri Valley, North Dakota) · Northern Great Plains (present-day North Dakota), practices documented late 19th–early 20th c.
Among the Hidatsa, the sunflower was the first seed put into the ground in spring, as soon as the ice broke on the Missouri, and the last harvested in autumn, it thus framed the whole garden season, alongside maize, beans, and squash. The seeds were roasted in clay pots then pounded into a fine meal. This meal went into a winter dish mixing sunflower meal, maize meal, beans, and dried squash; hand-pressed to release its oil, it also formed compact seed balls that hunters and warriors carried as travel rations against fatigue. The testimony is that of Maxidiwiac ('Buffalo Bird Woman'), born around 1839, who describes: 'The first seed that we planted in the spring was sunflower seed.'
Gilbert L. Wilson, Buffalo Bird Woman's Garden: Agriculture of the Hidatsa Indians (paroles de Maxidiwiac / Buffalo Bird Woman), 1917, texte intégral, University of Pennsylvania Digital Library.
A verbatim quotation verified in the primary text. An ethnographic account transcribed by an anthropologist; a domestic and food use, not ceremonial. The sunflower figures here as a nourishing crop in its own right, alongside the 'three sisters'.
Keep in mind
Using sunflower as a living stake for beans is traditional. Its allelopathic compounds have mainly been studied against weeds and wheat (Anjum and Bajwa, 2010): as a precaution, avoid digging its residues in before sowing wheat, but an effect on beans is not established. Tall and vigorous, it is best kept to rich, well-watered soils, without expecting a demonstrated benefit for the legume.
A note on rigour: many companion pairings are gardening folklore; this note sums up what the sources say, where there are any.