The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. 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 Washington should be looked at to figure out when to plant datura.

Planting Calendar for Datura

Frost tolerance for datura:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant datura a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

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

The last month that you can plant datura and expect a good harvest is probably August. You probably don't want to wait any later than that or else your datura may not have a chance to grow to maturity. Starting your datura indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Washington and it changes from year to year. Half of the time in Washington you get surprised by a frost after April 15 so make sure that you are ready to protect your datura 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.