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

One way of figuring out when it's possible to plant plectranthus is to consult the USDA zone info for Waltham.

Planting Calendar for Plectranthus

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

You should not plant plectranthus until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant plectranthus in Waltham is April. However, you really should wait until May 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. If you wait any later than that and your plectranthus may not have a chance to really do well. You can get started a little bit earlier by starting your plectranthus indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Waltham. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Waltham is not always accurate the actual date of last frost will vary from year to year. Half of the time in Waltham it frosts late in the year after April 15 so always be ready to cover your plectranthus if you have one of those late frosts.

USDA Zone Info for Waltham

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 Waltham

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