One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Charlestown you can determine when it's the best time to plant iberis by looking at the USDA zone info.

Planting Calendar for Iberis

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

Since iberis do well in moderate cold you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant iberis in Charlestown 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 iberis and expect a good harvest is probably September. You probably don't want to wait any later than that or else your iberis may not have a chance to really do well. You can get started a couple of weeks earlier by starting your iberis indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Charlestown. You can expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Charlestown may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Charlestown there is a last frost after April 15 be ready to cover your iberis if you have one of those late frosts.

USDA Zone Info for Charlestown

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 Charlestown

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