When to plant sage in Denver, Colorado

April 30 – May 14

Transplant outdoors · typical Denver year

Climate 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. Transplant sage outdoors 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.

Last spring freezeApril 301-in-10 after May 13

First fall freezeOctober 121-in-10 before Sep 28

Frost-free season≈ 165 daysmedian at 32°F

Hard freeze, 28°Apr 18 – Oct 21kills even hardy greens

USDA zone6a-10 to -5°F winter low — not frost timing

The Denver year

Start seeds indoorsMar 5 – Mar 19

Transplant outdoorsApr 30 – May 14

Direct-sow outdoorsApr 30 – May 14

indoors under lights
in the garden
frost-free season
1-in-10 years still freeze to May 13

Sage in Denver · freeze context from Denver Water Dept, CO, 1991–2020 normals.

Every method, with its sources

Start seeds indoors

Mar 5 – Mar 19

Wisconsin Horticulture says to start sage indoors 6 to 8 weeks before the average date of last frost, so sowing runs 8 to 6 weeks before the last spring freeze. Anchored to the median last spring freeze (Apr 30). University of Wisconsin-Madison Division of Extension, Wisconsin Horticulture · University of Maryland Extension

Transplant outdoors

Apr 30 – May 14

UMD Extension names sage among herbs started indoors and planted outside after the danger of frost has passed, which coincides with Wisconsin Horticulture's direct-sow date, so the window opens at the last spring freeze. Anchored to the median last spring freeze (Apr 30). University of Wisconsin-Madison Division of Extension, Wisconsin Horticulture · University of Maryland Extension

Direct-sow outdoors

Apr 30 – May 14

Wisconsin Horticulture gives a point rule — plant sage seed directly in the garden on the average date of last frost — which opens a two-week sowing span beginning at that date. Anchored to the median last spring freeze (Apr 30). University of Wisconsin-Madison Division of Extension, Wisconsin Horticulture · University of Maryland Extension

Variety assumption: Wisconsin Horticulture notes seed-grown sage may not flower the first year; culinary leaf harvest is unaffected.

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.

This week, not a typical year:

Crop rule sources (2)

University of Wisconsin-Madison Division of Extension, Wisconsin Horticulture: Sage, Salvia officinalis (accessed 2026-07-25)
"To grow from seed, either plant directly in the garden on the average date of last frost or start indoors 6 to 8 weeks before then."
University of Maryland Extension: Care of Herbs and Starting Herbs from Seed (accessed 2026-07-25)
"Basil, parsley, sage, marjoram, and many other herbs can be started indoors and planted outside after the danger of frost has passed."

Keep exploring

This crop, other cities

Related crops in Denver

Local overview