When to Plant Primroses in Milliken, CO

One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Milliken you can estimate when it's possible to plant primroses by referring to the USDA zone info.


Planting Calendar for Primroses

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

Since primroses are one of those plants that can tolerate quite a bit of cold weather you can plant them much earlier in the year than other frost tender plants.

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

The earliest that you can plant primroses in Milliken 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 primroses and expect a good harvest is probably September. You probably don't want to wait any later than that or else your primroses may not have a chance to fully mature. If you are starting your primroses indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Milliken the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Milliken is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Milliken you get surprised by a frost after April 15 so make sure that you are ready to cover your primroses if you have a surprise late frost.

USDA Zone Info for Milliken

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 Milliken

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