Hopi Black Dye

Sunflower

90d to harvest

Velvety, inky petals unfurl in late season, as if dusk has been gathered into a single, towering bloom—Hopi Black Dye delivers a dramatic, near-black presence with a softly velour-like texture. The flower heads are rich and substantial, making them a striking centerpiece in the garden while also offering abundant pollen for pollinators. Grow Hopi Black Dye for bold visual impact and a deep, memorable color story that carries from bud to bloom.

Crop Dates

Growing note: In frost-free Zone 10b, grow this cool-season crop during the cooler dry season (October–February).

Milestone	Date
Start Indoors	—
Climate	Frost-Free Climate
Transplant / Sow Outdoors	Oct 1st
Harvest Begins	Dec 30th
Harvest Ends	Feb 28th

Crop Details

Trait	Value
Days to Maturity	90
Sun Requirements	Full Sun
Growth Habit	Upright
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	70
Min Soil Temp (°F)	55
Min Night Temp (°F)	40
Harden Off (days)	Not Required

Frequently Asked Questions

What pests commonly attack Helianthus annuus (Hopi Black Dye), and what can I do if I see them?

Sunflower headworms and sunflower moth larvae can bore into developing flower heads and reduce seed quality. Inspect heads weekly as they form and remove any infested heads early; for ongoing pressure, use row cover until flowering and apply an approved Bt (Bacillus thuringiensis) product when larvae are small. Aphids may also cluster on new growth—spray with a strong jet of water and, if needed, use insecticidal soap targeted to the underside of leaves.

How often should I water Hopi Black Dye (Helianthus annuus) during the main growing period?

During vegetative growth and the run-up to bloom, keep the soil evenly moist but not soggy—typically about 1 inch of water per week, adjusted for rainfall and heat. Water deeply so moisture reaches the root zone, and let the top 1–2 inches of soil dry slightly between waterings to prevent root stress. Once heads are forming and filling, avoid letting the soil dry out completely; inconsistent moisture can stunt the head and reduce fullness.

How can I tell when Hopi Black Dye (Helianthus annuus) is ready to harvest?

Harvest at about 90 days when the back of the flower head turns yellow-brown and the bracts (the small leaves around the head) are mostly dried. The seeds should look plump and mature, and many of the outer seeds will detach easily when rubbed by hand. Cut heads and dry them in a warm, airy place until seeds are hard and fully dry, then thresh if you’re saving seed for dye use.