Before planting it is a good idea to find your USDA Zone info to figure out your garden 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 Portola Valley should be reffered to in order to estimate when it's a good idea to plant bishop's weed.

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.

Since bishop's weed do well in cold you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant bishop's weed in Portola Valley is January. However, you really should wait until February 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 October. Any later than that and your bishop's weed may not have a chance to fully mature. Starting your bishop's weed indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Portola Valley the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Portola Valley and it can change quite a bit from year to year. Since half of the time in Portola Valley there is a last frost after January 31 be ready to protect your bishop's weed if you have a late frost.

USDA Zone Info for Portola Valley

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Portola Valley

You may be interested in your other planting guides for Portola Valley.