One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Beaverton should be looked at to estimate when you can plant primroses.

Planting Calendar for Primroses

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

Primroses do well in cold which tells us that you can start planting them much earlier than other frost tender plants.

The earliest that you can plant primroses in Beaverton 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 primroses and expect a good harvest is probably September. Any later than that and your primroses may not have a chance to grow to maturity. You can get started a little bit earlier by starting your primroses indoors.

Last Frost Date

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

Always keep in mind that USDA zone info for Beaverton is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Beaverton you get a frost after March 15 so be sure to be ready to protect your primroses in the event of a late frost.

USDA Zone Info for Beaverton

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Beaverton

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