One of the best tools that you have as gardeners to help us determine 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.

You should be able to determine when it's the best time to plant phlox by using the USDA zone info for Carroll.

Planting Calendar for Phlox

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

Since phlox do well in moderate cold you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant phlox in Carroll 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 really do well. You can get started a few weeks earlier by starting your phlox indoors.

Last Frost Date

In Carroll the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

It's important to remember that USDA zone info for Carroll is just an average and the actual date of last frost is different every year. Since half of the time in Carroll there is a last frost after April 15 be ready to cover your phlox if you have a surprise late frost.

USDA Zone Info for Carroll

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Carroll

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