When to Plant Forget-Me-Not in Thornton, CO

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant forget-me-not in Thornton can be determined by checking out the USDA zone info.


Planting Calendar for Forget-Me-Not

Frost tolerance for forget-me-not: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Since forget-me-not are one of those plants that can tolerate a little bit of cold weather you can plant them a little bit earlier in the year than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant forget-me-not
Possibly ok, but a risky time to plant forget-me-not
Probably not a good time to plant forget-me-not

The earliest that you can plant forget-me-not in Thornton 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 forget-me-not and expect a good harvest is probably September. Any later than that and your forget-me-not may not have a chance to grow to maturity. If you are starting your forget-me-not indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Thornton the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -15°F.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Thornton and it changes from year to year. Half of the time in Thornton last frost occurs after April 15 so always be ready to cover your forget-me-not if you have a late frost.

USDA Zone Info for Thornton

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Thornton

You may be interested in your other planting guides for Thornton.