The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. 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 kale in Waltham should be estimated by checking out the USDA zone info.

Planting Calendar for Kale

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

Since kale do well in moderate cold you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant kale in Waltham 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 kale and expect a good harvest is probably September. If you wait any later than that and your kale may not have a chance to grow to maturity. If you are starting your kale indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Waltham. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Waltham is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Waltham last frost occurs after April 15 so make sure that you are prepared to cover your kale in the event of 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.