Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant impatiens in Waltham can be figured out by using the USDA zone info.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Impatiens require warm weather which means that you really should wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant impatiens 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 impatiens and expect a good harvest is probably August. If you wait any later than that and your impatiens may not have a chance to grow to maturity. Starting your impatiens indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Just be sure to remember that USDA zone info for Waltham may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Waltham last frost occurs after April 15 be ready to cover your impatiens 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.