One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant euphorbia in Castle Rock should be determined by reviewing 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 a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant euphorbia in Castle Rock 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. Any later than that and 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

In Castle Rock the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Castle Rock is an average the actual date of last frost changes from year to year. Since half of the time in Castle Rock it frosts late in the year after April 15 be ready to protect your euphorbia in the event of one of those late frosts.

USDA Zone Info for Castle Rock

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Castle Rock

You may be interested in your other planting guides for Castle Rock.