Before planting it is a good idea to find your USDA Zone info to determine 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.

The earliest that you can plant calliopsis in Mount Vernon can be figured out 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 has passed.

You should not plant calliopsis until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant calliopsis in Mount Vernon 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 really do well. You can get started a little bit earlier by starting your calliopsis indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Mount Vernon. It might get as low as -5°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Mount Vernon and it is different every year. Half of the time in Mount Vernon it frosts late in the year after April 15 so just be sure to be ready to cover your calliopsis in the event of a surprise late frost.

USDA Zone Info for Mount Vernon

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Mount Vernon

You may be interested in your other planting guides for Mount Vernon.