When to Plant Primroses in Zone 5b

One of the first steps you take when you are getting a good idea 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.

The first chance to plant primroses in Zone 5b should be figured out by using 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.

You can plant primroses a lot earlier in the year because they do well in cold.

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 Zone 5b 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. Any later than that and your primroses may not have a chance to grow to maturity. 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 Zone 5b 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.

Since the USDA zone info for Zone 5b may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 5b it frosts late in the year after April 15 so make sure that you are prepared to protect your primroses in the event of a surprise late frost.

USDA Zone Info for Zone 5b

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 Zone 5b

You may be interested in your other planting guides for Zone 5b.