🌼 Can I Plant Marigold in Seattle, WA?

2026 planting guide for Zone 8b · Last frost ~March 18 · Growing season ~242 days

⏳ WAIT — Temps borderline — ideal is 55°F+ overnight

Conditions are above the minimum safe threshold but still below ideal for Marigold. Overnight lows of 55°F+ would give much better results.

Planting window: Aug 6 – Aug 20
Wait a bit longer. Watch for overnight lows to reliably reach 55°F.
Live result based on current forecast for Seattle, WA · Updates every 6 hours
USDA Zone
8b
Last Spring Frost
~March 18
First Fall Frost
November 15
Growing Season
~242 days
Ideal Temp for Marigold
55–90°F
Frost Risk
⚠️ Sensitive

Growing Marigold in Seattle

Seattle's Zone 8b maritime climate is notoriously cool and cloudy, which means warm-season crops like tomatoes and peppers need all the help they can get. A south-facing wall or greenhouse extension is almost essential for tomatoes. On the plus side, cool-season crops like kale, lettuce, and peas absolutely thrive in Seattle's mild, moist conditions.

In Seattle (last frost around March 18), aim to direct sow or transplant marigold outside around April — approximately 2 weeks after your last expected frost. Starting seeds indoors 6 weeks before the last frost date gives you a significant head start.

Marigold thrives between 55°F and 90°F. It is frost-sensitive, meaning a single freeze at 32°F will damage or kill it — always wait until frost danger has fully passed. Expect 45–55 days from transplant to first harvest. Great companion plant — repels pests. Easy and fast-growing.

Frequently Asked Questions

When can I plant marigold in Seattle, WA?

In Seattle (last frost around March 18), aim to direct sow or transplant marigold outside around April — approximately 2 weeks after your last expected frost. For best results, start seeds indoors 6 weeks before that — giving you strong transplants ready to go out at the right time.

What is the USDA hardiness zone for Seattle?

Seattle, WA is in USDA Plant Hardiness Zone 8b. The last expected spring frost is around March 18, and the first fall frost arrives around November 15. This zone classification helps you understand which perennials survive winter and when annual vegetables can safely go outdoors.

Is it safe to plant marigold outside in Seattle right now?

That depends on the current weather forecast. Marigold needs temperatures above 40°F (ideally 55–90°F) to thrive. CanIPlant checks your real 7-day forecast and any active frost alerts to give you a live YES, NO, or WAIT answer — just enter your ZIP code.

Can I grow marigold in Seattle 2026?

Yes — Marigold grows well in Seattle, WA. With a Zone 8b climate and a growing season of ~242 days, Seattle is well-suited for warm-season crops like marigold. Just wait until after the last frost (around March 18) before moving plants outside.

Grow Marigold in Other Cities

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