Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Charlestown should be reviewed to estimate when it's possible to plant phlox.

Planting Calendar for Phlox

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

Phlox do well in mild cold which tells us that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant phlox 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 phlox and expect a good harvest is probably September. If you wait any later than that and your phlox may not have a chance to grow to maturity. Starting your phlox indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Charlestown is an average the actual date of last frost will vary from year to year. Since half of the time in Charlestown it frosts late in the year after April 15 be ready to protect your phlox in the event of 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.