Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of figuring out when it's possible to plant euphorbia is to consult the USDA zone info for Colville.

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.

Euphorbia do ok in mild cold which tells us that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant euphorbia in Colville 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 euphorbia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your euphorbia may not have a chance to grow to maturity. If you are starting your euphorbia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Colville the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Keep in mind that USDA zone info for Colville may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Colville last frost occurs after April 15 so just be sure to be ready to protect your euphorbia if you have one of those late frosts.

USDA Zone Info for Colville

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Colville

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