The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can determine when you can plant iceland poppy in Castle Rock by reviewing the USDA zone info.

Planting Calendar for Iceland Poppy

Frost tolerance for iceland poppy:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant iceland poppy just a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant iceland poppy in Castle Rock 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 iceland poppy and expect a good harvest is probably September. If you wait any later than that and your iceland poppy may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your iceland poppy indoors.

Last Frost Date

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

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Castle Rock and it changes from year to year. Half of the time in Castle Rock you get a frost after April 15 so always be ready to cover your iceland poppy if you have 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.