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.

It's possible to figure out when you can plant primula by looking at the USDA zone info for North Liberty.

Planting Calendar for Primula

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

Primula are one of those plants that can tolerate quite a bit of cold weather which means that you can start planting them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant primula in North Liberty 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 primula and expect a good harvest is probably September. Any later than that and your primula may not have a chance to grow to maturity. If you are starting your primula 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 April 15 in North Liberty. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for North Liberty is not always accurate and the actual date of last frost changes from year to year. Half of the time in North Liberty you get a frost after April 15 so make sure that you are prepared to protect your primula if you have a late frost.

USDA Zone Info for North Liberty

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 North Liberty

You may be interested in your other planting guides for North Liberty.