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.

In Irmo you can figure out when it's the best time to plant phlox by using the USDA zone info.

Planting Calendar for Phlox

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

Phlox can survive in mild cold which means that you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant phlox in Irmo 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. You probably don't want to wait any later than that or else your phlox may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your phlox indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Irmo. It might get as low as 10°F during the coldest months of winter.

Since the USDA zone info for Irmo is an average the actual date of last frost will vary from year to year. Half of the time in Irmo there is a last frost after March 15 so be sure to be ready to cover your phlox in the event of one of those late frosts.

USDA Zone Info for Irmo

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Irmo

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