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

By checking out the USDA zone info for Portola Valley you will be able to determine when it's a good idea to plant euphorbia.

Planting Calendar for Euphorbia

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

Since euphorbia are barely cold tolerant you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant euphorbia in Portola Valley 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 euphorbia and expect a good harvest is probably September. Any later than that and your euphorbia may not have a chance to grow to maturity. Starting your euphorbia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Portola Valley. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Portola Valley may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Portola Valley last frost occurs after January 31 so just be sure to be ready to protect your euphorbia in the event of one of those late frosts.

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.