One of the first steps you take when you are determining your gardening schedule is find your 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.

You should be able to figure out when it's the best time to plant tomatos by using the USDA zone info for Waltham.

Planting Calendar for Tomatos

Frost tolerance for tomatos:	Not tolerant of frost.
When to plant:	After the last frost.

Since tomatos require warm weather it's important to wait until after the last frost before you can plant them.

The earliest that you can plant tomatos 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 tomatos and expect a good harvest is probably August. If you wait any later than that and your tomatos may not have a chance to really do well. You can get started a couple of weeks earlier by starting your tomatos indoors.

Last Frost Date

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

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Waltham and it is different every year. Since half of the time in Waltham you get surprised by a frost after April 15 be ready to protect your tomatos in the event of a surprise late frost.

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.