One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of estimating when it's the best time to plant primroses is to check out the USDA zone info for Caledonia.

Planting Calendar for Primroses

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

Primroses tend to make it in a bit of cold which tells us that you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant primroses in Caledonia 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. If you wait 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

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

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Caledonia and it is different every year. Since half of the time in Caledonia it frosts late in the year after April 15 be ready to protect your primroses in the event of one of those late frosts.

USDA Zone Info for Caledonia

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 Caledonia

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