One of the first steps you take when you are estimating 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.

You can estimate when it's possible to plant lithospermum in Washougal by reviewing the USDA zone info.

Planting Calendar for Lithospermum

Frost tolerance for lithospermum:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's not a good idea to plant lithospermum until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant lithospermum in Washougal 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 lithospermum and expect a good harvest is probably August. Any later than that and your lithospermum may not have a chance to fully mature. If you are starting your lithospermum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Washougal. In the coldest months of winter you can expect an average low temperature of 15°F.

It's important to remember that USDA zone info for Washougal may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Washougal you get surprised by a frost after March 15 be ready to protect your lithospermum if you have a surprise late frost.

USDA Zone Info for Washougal

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 Washougal

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