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When to plant in Ken Caryl, CO

USDA Zone 6a

Everything below — frost dates, hardiness zone, and what to plant when in Ken Caryl, Colorado — is derived from the closest NOAA station with complete climate normals.

Zone 6a means Ken Caryl sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.

Station · MARSTON FLTR PLT · 6.4 km
Last spring frost
May 2
50% chance · 32°F
First fall frost
October 11
50% chance · 32°F
Growing season
162 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Ken CarylA year-band showing 32°F frost risk from January to December for Ken Caryl: last spring frost around May 2, first fall frost around October 11, about 162 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

MARSTON FLTR PLT · 1991–2020

The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Ken Caryl’s own odds, recorded at MARSTON FLTR PLT.

Frost-probability curves for Ken CarylProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around May 2 and the first fall frost around October 11, giving about 162 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FMay 29May 12Apr 30Sep 17Oct 2Oct 15
32°FMay 17May 2Apr 20Sep 27Oct 11Oct 23
28°FMay 7Apr 23Apr 8Oct 6Oct 21Nov 5

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19
Fall sowopen now
Rutabaga
July 5July 19
Fall sowopen now
Broccoli
July 19August 2
Fall sowopen now
Cabbage
July 19August 2
Fall sowopen now
Carrot
July 19August 2
Fall sowopen now
Cauliflower
July 19August 2
Fall sowopen now
Napa Cabbage
July 19August 16
Fall sowin 14 days
Beet
August 2August 16
Fall sowin 14 days
Collards
August 2August 30
Fall sowin 14 days
Endive
August 2August 16
Fall sowin 14 days
Escarole
August 2August 16
Fall sowin 14 days
Fennel (Bulb)
August 2August 16
Fall sowin 14 days
Kale
August 2August 30
Fall sowin 14 days
Kohlrabi
August 2August 30
Fall sowin 14 days
Peas
August 2August 16
Fall sowin 14 days
Radicchio
August 2August 16
Fall sowin 14 days
Swiss Chard
August 2August 16
Fall sowin 14 days
Turnip
August 2August 30
Fall sowin 28 days
Arugula
August 16September 13
Fall sowin 28 days
Bok Choy
August 16August 30
Fall sowin 28 days
Chervil
August 16September 13
Fall sowin 28 days
Cilantro
August 16September 13
Fall sowin 28 days
Claytonia (Miner's Lettuce)
August 16September 13
Fall sowin 28 days
Corn Salad (Mâche)
August 16September 13
Fall sowin 28 days
Gai Lan (Chinese Broccoli)
August 16August 30
Fall sowin 28 days
Lettuce
August 16September 13
Fall sowin 28 days
Mizuna
August 16September 13
Fall sowin 28 days
Mustard Greens
August 16September 13
Fall sowin 28 days
Radish
August 16September 13
Fall sowin 28 days
Shungiku (Edible Chrysanthemum)
August 16August 30
Fall sowin 28 days
Spinach
August 16September 13
Fall sowin 28 days
Tatsoi
August 16September 13

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Ken Caryl, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 16 km · complete 32°F normals

When stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.

MARSTON FLTR PLT
Primary
6 km · 1710 m elevation
SPRING
May 2
FALL
Oct 11
KASSLER
10 km · 1703 m elevation
SPRING
May 8
FALL
Oct 3
STRONTIA SPRINGS DAM
16 km · 1780 m elevation
SPRING
May 16
FALL
Sep 29

Ken Caryl planting FAQ

When is the last spring frost in Ken Caryl, CO?

On average, the last spring frost in Ken Caryl is around May 2 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.

When is the first fall frost in Ken Caryl, CO?

In Ken Caryl, the first 32°F freeze of fall lands around October 11 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Ken Caryl in?

Ken Caryl is in USDA hardiness zone 6a. In zone 6a, winters are moderate — most common vegetables grow well in season.

How long is the growing season in Ken Caryl?

There are roughly 162 frost-free days in Ken Caryl (a moderate growing season), running from the average last frost around May 2 to the first fall frost near October 11.

When should I plant tomatoes in Ken Caryl?

In Ken Caryl, start tomato seeds indoors around March 7–March 21, then transplant seedlings outdoors around May 9 once the danger of frost has passed.

Planting reminders

Never miss a window in Ken Caryl

An email when it’s time to start seeds, transplant, and sow — timed to Ken Caryl’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at MARSTON FLTR PLT, 6 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Ken Caryl, CO — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00055402. Retrieved from https://blissgarden.com/colorado/ken-caryl.
When to Plant in Ken Caryl, CO — Frost Dates & Zone 6a — BlissGarden