One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

The USDA zone info for Mount Vernon can be read to figure out when it's a good idea 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 are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant phlox in Mount Vernon 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. Any later than that and your phlox may not have a chance to really do well. If you are starting your phlox indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Mount Vernon. It might get as low as -5°F during the coldest months of winter.

Just be sure to remember 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 changes from year to 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 phlox if you have one of those late frosts.

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.