One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant plectranthus in Zone 4a should be determined by looking at the USDA zone info.

Planting Calendar for Plectranthus

Frost tolerance for plectranthus:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since plectranthus do not do well in cold weather you must wait until after the last frost has passed before you can plant them.

The earliest that you can plant plectranthus in Zone 4a is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant plectranthus and expect a good harvest is probably August. Any later than that and your plectranthus may not have a chance to grow to maturity. Starting your plectranthus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Zone 4a the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -30°F.

It's important to remember that USDA zone info for Zone 4a is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Zone 4a it frosts late in the year after May 15 so always be ready to cover your plectranthus in the event of a late frost.

USDA Zone Info for Zone 4a

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Zone 4a

You may be interested in your other planting guides for Zone 4a.