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.

One way of estimating when it's possible to plant euphorbia is to refer to the USDA zone info for Watertown.

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 are barely cold tolerant which means that you can plant them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant euphorbia in Watertown 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 euphorbia and expect a good harvest is probably August. Any later than that and your euphorbia may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your euphorbia indoors.

Last Frost Date

In Watertown the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -30°F.

Always keep in mind that USDA zone info for Watertown is not always accurate and the actual date of last frost is different every year. Since half of the time in Watertown there is a last frost after May 15 be ready to protect your euphorbia in the event of one of those late frosts.

USDA Zone Info for Watertown

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°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 -25°F.

Plants to Grow in Watertown

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