When to plant cilantro in Denver, Colorado
April 2 – April 16
Direct-sow outdoors · typical Denver yearClimate basis: NOAA station Denver Water Dept, CO (USC00052223), 2 mi (3 km) from downtown Denver (ZCTA 80202 centroid), elevation 5228 ft, on the 1991–2020 climate normals. Direct-sow cilantro from approximately the dates above, anchored to the median last spring 32°F freeze (April 30). One year in ten still freezes after May 13.
The Denver year
- indoors under lights
- in the garden
- frost-free season
- 1-in-10 years still freeze to May 13
Every method, with its sources
Direct-sow outdoors
Apr 2 – Apr 16Oklahoma State: sow two to four weeks before the last spring frost (with a second sowing in late summer for fall harvest). Cilantro bolts in heat — sow early. Anchored to the median last spring freeze (Apr 30). Oklahoma State University Extension
Start seeds indoors
Not calculatedCilantro is tap-rooted and resents transplanting; the cited guide times direct sowing only.
Transplant outdoors
Not calculatedThe cited extension guides do not time an outdoor transplanting window for this crop.
Fall planting
Not calculatedNo source-backed fall planting rule exists for this crop in the registry, so no fall window is calculated.
Variety assumption: Leaf harvest begins about 40–50 days from sowing; bolts quickly in warm weather.
These windows describe typical years (1991–2020 climate normals), not this year's forecast. Freezes happen outside them — especially in frost pockets, valleys, and urban edges. Watch the forecast before committing tender plants.
Crop rule sources (1)
- Oklahoma State University Extension: Culinary Herbs for Oklahoma Gardens: Culture, Use and Preservation (accessed 2026-07-24)Table 1 planting times relative to last spring frost for common herbs.