Growing Cilantro in Canada — Beat the Bolt
Cilantro planted in the heat of a Canadian summer bolts to flower within days — not a failure, just the plant's normal response to heat. Grow it as a spring and fall crop instead, and it's genuinely easy.
"My cilantro keeps going to seed right away" is one of the most common herb complaints in Canadian gardens — and it's almost always a timing problem, not a growing mistake. Cilantro is a cool-season crop, closer in behaviour to spinach or lettuce than to sun-loving basil.
Plant it when it's supposed to grow — spring and fall — and cilantro is straightforward. Plant it in the heat of midsummer, and it will bolt no matter what you do.
Growing cilantro in Canada: a cool-season crop that bolts within days once temperatures pass ~25–27°C. Grow it in spring and fall, not midsummer. Direct sow — it has a taproot and transplants poorly. Succession sow every 2–3 weeks for continuous leaf. Bolted plants aren't wasted — let them flower and the seeds become coriander.
When should you plant cilantro where you garden?
Get your city's frost dates, indoor seed-starting dates, and this week's planting jobs — three free tools.
🌱 Need seeds? West Coast Seeds (a BC company) sells untreated, Canadian-grown herb seed — including bolt-resistant cilantro varieties.
🥦 Shop herb seeds at West Coast Seeds →Grow It Like Spinach, Not Basil
Cilantro shares shelf space with warm-season herbs like basil at Canadian garden centres, but its actual growing behaviour is closer to cool-season greens. Heat above roughly 25–27°C is the direct trigger for bolting — the plant senses summer coming and rushes to flower and set seed before conditions get too hot to support it.
A cilantro planting made in the heat of July will bolt within days — no growing technique prevents this. The fix is timing, not technique: plant in spring and again in late summer, and skip the midsummer sowing entirely.
Direct sow in early spring as soon as soil can be worked (cilantro handles cool soil and light frost fine), then again in late summer for a fall crop that grows through cooling autumn weather without racing to flower.
Keeping Cilantro Coming
Succession sow every 2–3 weeks
Even in the cooler spring window, one planting only gives a few weeks of good leaf. Sowing a new round every 2–3 weeks keeps a young, non-bolted planting always available.
Choose a bolt-resistant variety
Varieties bred specifically for slower bolting (commonly sold as Santo, Calypso, or Slow Bolt) buy meaningfully more harvest time than a standard variety, especially useful for a marginal early-summer planting.
A bolted plant isn't wasted — it becomes coriander
Cilantro (the leaf) and coriander (the seed) are the same plant. Let a bolted planting flower and mature its seed heads, then harvest and dry the seeds — a genuinely useful spice from a plant that's "gone to seed" anyway.
Frequently Asked Questions
Why does my cilantro bolt so fast?
Heat above ~25–27°C triggers bolting. It's a cool-season crop — grow it in spring and fall, not midsummer.
When should I plant cilantro in Canada?
Early spring as soon as soil can be worked, and again in late summer for a fall crop. Skip midsummer sowings.
What's the difference between cilantro and coriander?
Same plant — cilantro is the fresh leaf, coriander is the dried seed harvested after it flowers.