One of the first steps you take when you are determining 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 estimate when it's the best time to plant calliopsis in Roma by looking at the USDA zone info.

Planting Calendar for Calliopsis

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

It's probably a bad idea to plant calliopsis until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant calliopsis in Roma 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 calliopsis and expect a good harvest is probably September. You probably don't want to wait any later than that or else your calliopsis may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your calliopsis indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Roma. In the coldest months of winter you can expect an average low temperature of 25°F.

Just be sure to remember that USDA zone info for Roma is not always accurate and the actual date of last frost is different every year. Half of the time in Roma there is a last frost after February 15 so just be sure to be ready to protect your calliopsis if you have one of those late frosts.

USDA Zone Info for Roma

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Roma

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