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

The first opportunity to plant primula in Green River can be figured out by referring to 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 very cold tolerant you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant primula in Green River 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. You probably don't want to wait any later than that or else your primula may not have a chance to fully mature. You can get started a little bit earlier by starting your primula indoors.

Last Frost Date

In Green River the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -25°F.

Remember that USDA zone info for Green River is just an average and the actual date of last frost changes from year to year. Since half of the time in Green River there is a last frost after May 15 be ready to cover your primula if you have a surprise late frost.

USDA Zone Info for Green River

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 Green River

You may be interested in your other planting guides for Green River.