The USDA Zone info is a great tool for gardeners to help us determine your gardening 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 Frederick should be reviewed to determine when it's the best time 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.

Since phlox are moderately cold tolerant you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant phlox in Frederick 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 fully mature. Starting your phlox indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Frederick the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Frederick is just an average and the actual date of last frost changes from year to year. Half of the time in Frederick there is a last frost after April 15 so just be sure to be ready to protect your phlox if you have one of those late frosts.

USDA Zone Info for Frederick

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Frederick

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