Frost Dates for Montrose, CO 81401

Last spring frost May 13 · First fall frost October 6 · 146 frost-free days · USDA Zone 6b

Frost probability for 81401

Frost10%50%90%
Spring (last frost)June 2May 13April 28
Fall (first frost)September 21October 6October 21

Dates come from NOAA 1971–2000 freeze probabilities at the nearest reporting station (40.0 km away); the 50% date is the median year.

Frost dates by ZIP code in Montrose, CO

ZIPLast spring frost (50%)First fall frost (50%)Zone
81401May 13October 66b
81403June 25September 36a

Month by month in Montrose

MonthWhat to do
JanuaryPlan your garden layout and order seeds. Research varieties suited to your frost dates.
FebruaryStart the slowest-growing crops indoors: onions, leeks, and celery (10–12 weeks before last frost).
MarchStart peppers and eggplant indoors 8–10 weeks before your last frost (around May 13). Start tomatoes about two weeks later, 6–8 weeks before last frost.
AprilStart herbs, basil, and squash indoors (4–6 weeks before frost). Direct sow peas, spinach, and lettuce if soil is workable.
MayLast frost around May 13. Transplant cold-hardy crops (broccoli, kale, cabbage). Harden off tomato and pepper seedlings.
JuneFrost has passed. Transplant tomatoes, peppers, and basil outdoors. Direct sow beans, cucumbers, squash, and zucchini.
JulySuccession plant lettuce and greens. Keep beds weeded and watered consistently.
AugustHarvest regularly to encourage production. Monitor for pests and disease.
SeptemberFirst fall frost approaching (around October 6). Transplant fall brassicas. Sow spinach, arugula, and radishes.
OctoberFirst frost around October 6. Harvest tomatoes and peppers before frost. Cover cold-hardy crops with row covers to extend the season.
NovemberHarvest remaining cold-hardy crops: kale, carrots, and beets. Plant garlic bulbs for next year.
DecemberClean up spent plants. Add compost to beds. Rest, review, and plan next year's garden.

What grows in a 146-day season

Frequently Asked Questions

What is the last frost date for Montrose, CO (ZIP 81401)?

The median last spring frost date for Montrose, CO (ZIP code 81401) is around May 13. This is the 50th-percentile date — meaning half of all years see frost end before this date. Use the 10% and 90% dates to understand the full range of risk in your area.

What is the first fall frost date in Montrose, CO?

The median first fall frost date for Montrose, CO is around October 6. Plan to harvest or protect frost-sensitive crops like tomatoes and peppers at least a week before this date to avoid losses.

How long is the growing season in Montrose, CO?

The frost-free growing season in Montrose is about 146 days. This window — from your last spring frost to your first fall frost — is when warm-season vegetables thrive. Cold-hardy crops like kale, spinach, and peas can extend your season by weeks on either side.

What USDA hardiness zone is Montrose, CO?

Based on frost date patterns, Montrose falls approximately in 6b. USDA hardiness zones are determined by average annual minimum winter temperatures and guide both plant selection and planting timing for your location.

When should I start tomatoes indoors in Montrose, CO?

Start tomato seeds indoors 6–8 weeks before your last frost date (around May 13). For Montrose, that's roughly March 18 to April 1. Transplant outdoors 1–2 weeks after your last frost.

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