One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Riverside you can figure out when you can plant euphorbia by referring to the USDA zone info.

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 do ok in moderate cold you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant euphorbia in Riverside 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 really do well. You can get started a little bit earlier by starting your euphorbia indoors.

Last Frost Date

The average date of last frost is April 15 in Riverside. You can expect an average low temperature of -10°F in the coldest months of winter.

Always 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 Riverside and it will vary from year to year. Half of the time in Riverside you get a frost after April 15 so make sure that you are prepared to cover your euphorbia if you have one of those late frosts.

USDA Zone Info for Riverside

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 Riverside

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