Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Madison you can determine when it's the best time to plant primula by using the USDA zone info.

Planting Calendar for Primula

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

Since primula are one of those plants that can tolerate quite a bit of cold weather you can plant them quite a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant primula in Madison is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant primula and expect a good harvest is probably August. Any later than that and your primula may not have a chance to fully mature. If you are starting your primula indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Madison. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Madison is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Madison there is a last frost after May 15 be ready to protect your primula if you have one of those late frosts.

USDA Zone Info for Madison

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Madison

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