Morning Glories in Denver: Annuals That Self-Seed Reliably

They Die at Frost, But Return from Seed

Morning glories are true annuals in Zone 5—they perish at the first hard freeze. But they're prolific self-seeders. Seeds drop in fall, overwinter in the soil, and germinate the following spring, creating the illusion of perennial persistence.

Growing Tips for Success

• Sow seeds directly after the last spring frost.
• Amend soil with compost or peat moss.
• Fertilize with a high-phosphorus product to maximize blooms.
• Expect flowers from late August through October.

Neighbors growing the same variety year after year are likely seeing self-sown seedlings—or simply replanting their favorite variety (Heavenly Blue is a classic).