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.

In Washington you can determine when it's possible to plant diascia by referring to the USDA zone info.

Planting Calendar for Diascia

Frost tolerance for diascia:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Diascia do well in moderate cold which means that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant diascia 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 diascia and expect a good harvest is probably September. Any later than that and your diascia may not have a chance to fully mature. Starting your diascia indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Washington. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Washington may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Washington you get a frost after April 15 so always be ready to protect your diascia in the event of a surprise late frost.

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.