When to Plant Primroses in Gladstone, OR

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's a good idea to plant primroses in Gladstone by reviewing 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 a lot earlier in the year than more sensitive 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 Gladstone 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 little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Gladstone. You should expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Gladstone is not always accurate the actual date of last frost is different every year. Since half of the time in Gladstone there is a last frost after March 15 be ready to protect your primroses if you have one of those late frosts.

USDA Zone Info for Gladstone

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)March 15
Average Date of First Frost (fall)November 15
Lowest Expected Low15°F
Highest Expected Low20°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 20°F.

Plants to Grow in Gladstone

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