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

One way of making a decision about when it's possible to plant bishop's weed is to consult the USDA zone info for Walla Walla.

Planting Calendar for Bishop's Weed

Frost tolerance for bishop's weed:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Bishop's Weed can survive in cold weather which tells us that you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant bishop's weed in Walla Walla 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 bishop's weed and expect a good harvest is probably September. You probably don't want to wait any later than that or else your bishop's weed may not have a chance to really do well. You can get started a couple of weeks earlier by starting your bishop's weed indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Walla Walla. It might get as low as 0°F during the coldest months of winter.

It's important to remember that USDA zone info for Walla Walla is not always accurate and the actual date of last frost is different every year. Since half of the time in Walla Walla it frosts late in the year after April 15 be ready to protect your bishop's weed in the event of one of those late frosts.

USDA Zone Info for Walla Walla

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Walla Walla

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