When to Plant Alyssum in Estes Park, CO

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Estes Park should be read to determine when it's possible to plant alyssum.


Planting Calendar for Alyssum

Frost tolerance for alyssum: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Alyssum can survive in pretty solid cold which means that you can plant them quite a bit earlier in the year than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant alyssum
Possibly ok, but a risky time to plant alyssum
Probably not a good time to plant alyssum

The earliest that you can plant alyssum in Estes Park is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant alyssum and expect a good harvest is probably September. Any later than that and your alyssum may not have a chance to fully mature. If you are starting your alyssum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Estes Park. In the coldest months of winter you should expect an average low temperature of -20°F.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Estes Park and it will vary from year to year. Since half of the time in Estes Park you get surprised by a frost after April 15 be ready to protect your alyssum in the event of one of those late frosts.

USDA Zone Info for Estes Park

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Estes Park

You may be interested in your other planting guides for Estes Park.