One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

The USDA zone info for Addison should be reffered to in order to determine when it's possible to plant primula.

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 much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant primula in Addison 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. You probably don't want to wait any later than that or else 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 few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Addison may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Addison last frost occurs after April 15 so always be ready to cover your primula in the event of a late frost.

USDA Zone Info for Addison

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 Addison

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