Growing Cosmos in Zone 5B

Cosmos are elegant, easy flowers that thrive in poor soil and attract pollinators all season.

Zone 5B has a moderate growing season. Most crops do well here with proper timing around frost dates.

Top Growing Tips

• Actually perform better in lean soil — don’t over-fertilize
• Direct sow after frost; seeds germinate in 7-10 days
• Tall varieties (4-6 feet) may need staking
• Deadhead to prolong blooming or let self-seed for next year
• Chocolate cosmos has a genuine chocolate scent (but is more tender)

Companion Planting

Good companions: vegetables and herbs — attracts beneficial insects

Avoid planting near: none — cosmos are universally friendly

Harvest Timeline

Flowering in 60-90 days from seed; excellent cut flower

About Zone 5B

USDA Hardiness Zone 5B has an average last spring frost around Apr 18 and first fall frost around Oct 13. All planting dates above are calculated from these frost dates. Your specific location may vary — check with your local extension office for the most accurate dates.