One of the first steps you take when you are getting a good idea your gardening schedule is find your 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.

One way of making a decision about when you can plant primula is to consult the USDA zone info for Washington.

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 means that you can plant them a quite a bit earlier than more sensitive plants.

The earliest that you can plant primula in Washington 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. If you wait any later than that and your primula may not have a chance to grow to maturity. Starting your primula indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Washington. It might get as low as 10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Washington is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Washington you get a frost after March 15 be ready to protect your primula in the event of a surprise late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Washington

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