Request a FREE 2018 Seed Catalog and Planting Guide

Sunflower - Mammoth Grey Stripe
Sunflower - Mammoth Grey Stripe

Sunflower - Mammoth Grey Stripe

Helianthus annuus

Long-blooming, large-headed, archetypal giant sunflower. Easy-to-grow. Sturdy 6-12' stalks with big yellow-petaled flowers. Often grown for their meaty seeds, good for roasting or bird seed. Direct seed in full sun after danger of frost. Summer-fall blooming. Annual.  

Regular price $2.75 $2.75 Sale

Average Seed / oz Seed / 100' Row Average Yield / 100' Row Days to Harvest
300 1 oz NA 80-120
Planting Season Ideal Soil Temp Sun Frost Tolerance
After Last Frost 65-85°F Full Sun Frost Sensitive
Sowing Method Seed Depth Direct Seed Spacing Seeds Per Packet
Transplant or Direct Seed 1" 4-16" 17
Mature Spacing Days to Sprout Production Cycle Seed Viability
8-12" 5-12 Annual 4-6 years

Site Selection

Sunflower is a frost sensitive annual that prefers full sun and well-drained soil with low to moderate moisture. Drought tolerant once established.


Direct seed outdoors once the danger of frost has passed. Optimum soil temperature for germination is 65-85˚F. Sow 1" deep and 4-6" apart. Seeds will sprout in 5-12 days. Thin so mature plants are 8-10" apart.

Customer Reviews

Based on 2 reviews Write a review