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

In Washington you can figure out when you can plant mimulus by referring to the USDA zone info.

Planting Calendar for Mimulus

Frost tolerance for mimulus:	Not tolerant of frost.
When to plant:	After the last frost.

Since mimulus do not do well in cold weather it is important to wait until after the last frost before you can plant them.

The earliest that you can plant mimulus in Washington is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant mimulus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your mimulus may not have a chance to really do well. If you are starting your mimulus indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Washington. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Washington is an average and the actual date of last frost changes from year to year. Half of the time in Washington you get a frost after April 15 so make sure that you are prepared to cover your mimulus in the event of one of those late frosts.

USDA Zone Info for Washington

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 Washington

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