The USDA Zone info is a great tool for gardeners to help us determine your gardening 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 determine when it's a good idea to plant primula by reviewing the USDA zone info for West Richland.

Planting Calendar for Primula

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

Primula are very cold tolerant which tells us that you can plant them much earlier than other frost tender plants.

The earliest that you can plant primula in West Richland 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 fully mature. Starting your primula indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in West Richland. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for West Richland is just an average the actual date of last frost will vary from year to year. Since half of the time in West Richland there is a last frost after April 15 be ready to protect your primula in the event of a late frost.

USDA Zone Info for West Richland

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in West Richland

You may be interested in your other planting guides for West Richland.