When to Start Cilantro Seeds: Indoor & Outdoor Timing

By Paul Smith, pemdasgarden.com

Timing is the whole game with cilantro. Sow at the wrong moment and you get three weeks of leaves before flowers; sow at the right moment and you harvest for months. This calendar-style guide answers exactly when to start cilantro seeds — indoors, outdoors, spring, and fall — so every sowing lands in the cool weather cilantro loves.

The Short Answer

Direct-sow cilantro outdoors 2 to 3 weeks before your last spring frost, then succession-sow every 2 to 3 weeks until about 40 days before sustained summer heat. Sow again 6 to 8 weeks before your first fall frost for an autumn harvest. Indoor starting is possible but rarely worth it — cilantro's taproot resents transplanting, and moved seedlings bolt faster.

Spring Sowing Dates by Zone

• Zones 3-4: late April to May, as soon as soil is workable; seedlings handle light frost.
• Zones 5-6: late March to April, 2 to 3 weeks before last frost.
• Zones 7-8: February to March; spring season is short, so start early and plan a big fall planting.
• Zones 9-10: fall through winter is prime time — sow October through February and skip summer entirely.

Soil temperature matters more than air temperature: cilantro germinates best with soil between 55 and 75°F. A simple soil thermometer removes the guesswork.

Fall Sowing: The Better Season

Many gardeners get their best cilantro in fall. Cooling temperatures and shortening days naturally delay bolting, so fall-sown plants often out-produce spring ones. Sow 6 to 8 weeks before your first expected fall frost — roughly August for most temperate regions, September where autumns run long. A cold frame or row cover stretches the harvest into early winter.

Succession Sowing Schedule

One sowing yields about 3 to 4 weeks of prime leaves. The fix: sow a small new patch every 2 to 3 weeks through the cool season. Mark it on the calendar like an appointment — gardeners who "sow once and hope" are the ones who complain cilantro always bolts. Stop successions roughly 40 days before your area's typical stretch of 85°F+ days, then resume when nights cool back down.

Should You Start Cilantro Indoors?

Honestly, usually not. Cilantro grows a taproot quickly, and any check in growth from transplanting reads as stress — which accelerates bolting, the exact problem you are trying to avoid. If you must start indoors (very short seasons), sow in biodegradable pots or soil blocks 3 to 4 weeks before transplanting, and move seedlings out while small, disturbing roots as little as possible. For most gardeners, direct sowing wins on every measure: less work, stronger plants, later bolting.

Common Timing Mistakes

• Sowing by the calendar alone instead of soil temperature and your actual frost dates.
• One big spring sowing with no successions — a 3-week harvest, then flowers.
• Starting indoors in tiny cells and transplanting late, which nearly guarantees instant bolting.
• Skipping the fall crop, which is often the highest-quality cilantro of the year.
• Sowing into warming soil above 75°F and blaming the seed when germination is spotty.

Garden tools that help: count back from your frost date with the Seed Starting Calculator, and confirm your hardiness zone with the Gardening Zone Lookup on our gardening tools hub.

Frequently Asked Questions

What month do you plant cilantro?

It depends on your zone: March-April in zones 5-6, February-March in zones 7-8, and October-February in zones 9-10. Fall sowing (usually August) suits almost every region.

Can I sow cilantro in summer?

Only with slow-bolt varieties, deep afternoon shade, and modest expectations. For most gardeners, summer sowing is a poor investment — wait for the fall window.

How late can I sow cilantro in fall?

Up to about 4 weeks before your first hard freeze if you protect with row cover; plants overwinter in mild climates and regrow in early spring.

Does cilantro need light to germinate?

No — sow 1/4 inch deep. Consistent moisture matters far more than light at the seed stage.

Keep growing: Shop cilantro seeds and read the full how to grow cilantro from seed guide, browse all herb seeds, compare timing with parsley, or return to the Growing Guides hub.