Before planting it is a good idea to find your USDA Zone info to figure out your garden 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 estimate when it's possible to plant calliopsis in Littleton by using the USDA zone info.

Planting Calendar for Calliopsis

Frost tolerance for calliopsis:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You really shouldn't plant calliopsis until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant calliopsis in Littleton 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 calliopsis and expect a good harvest is probably August. If you wait any later than that and your calliopsis may not have a chance to fully mature. You can get started a little bit earlier by starting your calliopsis indoors.

Last Frost Date

The average date of last frost is April 15 in Littleton. In the coldest months of winter you can expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Littleton is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Littleton there is a last frost after April 15 be ready to protect your calliopsis if you have a late frost.

USDA Zone Info for Littleton

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 Littleton

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