One of the best tools that you have as gardeners to help us estimate 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 Marshall can be read to determine when you can plant tall phlox.

Planting Calendar for Tall Phlox

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

Tall Phlox are moderately cold tolerant which means that you can start planting them earlier than more sensitive plants.

The earliest that you can plant tall phlox in Marshall 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 tall phlox and expect a good harvest is probably September. Any later than that and your tall phlox may not have a chance to grow to maturity. If you are starting your tall phlox indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Marshall. It might get as low as -10°F during the coldest months of winter.

Keep in mind that USDA zone info for Marshall is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Marshall it frosts late in the year after April 15 so always be ready to protect your tall phlox if you have a surprise late frost.

USDA Zone Info for Marshall

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Marshall

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