Skip to product information
1 of 3

Mammoth Sunflower

Mammoth Sunflower

SKU:1039

This giant among sunflowers is a fast grower whose single stalk can reach 12' tall and produces one 10"-12" flower! Not fussy about soil, it's very easy to grow and drought tolerant. Grow in a tight row to make an attractive screen. Sow monthly for continual bloom.

Regular price $2.69
Regular price Sale price $2.69
Sale Sold out
Shipping calculated at checkout.

View full details
  • Variety Info
  • Sowing Info
  • Growing Info
  • Learn More

Variety Info

Family: Asteraceae

Type: Sunflower (Learn more)

Native: North America

Hardiness: Annual

Exposure: Full sun

Bloom Period: Summer to frost

Plant Dimensions: 6'–12' tall

Variety Info: Up to 12"-wide flowers with yellow petals and a brown center. Single type.

Attributes: Attracts Pollinators, Cut Flower, Drought Tolerant, Heat Tolerant, Edible Flower

Sowing Info

When to Sow Outside: RECOMMENDED. 1 to 2 weeks after your average last frost date.

When to Start Inside: 2 to 4 weeks before your average last frost date. Sunflowers are senstive to root disturbance; sow in biodegradable pots that can be planted directly in the ground.

Days to Emerge: 10–15 days

Seed Depth: ¼"–½"

Seed Spacing: A group of 3 seeds every 24"

Thinning: When 3" tall, thin to 1 every 24"

Growing Info

Harvesting: Seeds are ready to harvest when the back of the head has dried and turned brown, about 4 weeks after the flowers have been pollinated. Petals will have wilted and fallen off, and the seeds will be plump, and colored white with gray/black stripes. Seeds ripen around the outside of the flower first; the ones in the center will ripen last. Average yield is approximately 1 pound per head.