When to Plant Bells of Ireland in Castle Rock, CO

One of the first steps you take when you are estimating 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.

You can figure out when you can plant bells of ireland in Castle Rock by reviewing the USDA zone info.


Planting Calendar for Bells of Ireland

Frost tolerance for bells of ireland: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Since bells of ireland do ok in moderate cold you can plant them a bit earlier in the year than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant bells of ireland
Possibly ok, but a risky time to plant bells of ireland
Probably not a good time to plant bells of ireland

The earliest that you can plant bells of ireland 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 bells of ireland and expect a good harvest is probably August. Any later than that and your bells of ireland may not have a chance to grow to maturity. Starting your bells of ireland indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Castle Rock is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Castle Rock there is a last frost after April 15 so make sure that you are ready to protect your bells of ireland if you have a late frost.

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.