The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to estimate when to plant petunias by using the USDA zone info for Haverhill.

Planting Calendar for Petunias

Frost tolerance for petunias:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant petunias a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant petunias in Haverhill is March. However, you really should wait until April if you don't want to take any chances.

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

Last Frost Date

On average the last frost is on April 15 in Haverhill. In the coldest months of winter you should expect an average low temperature of -10°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Haverhill and it is different every year. Half of the time in Haverhill there is a last frost after April 15 so make sure that you are prepared to cover your petunias in the event of one of those late frosts.

USDA Zone Info for Haverhill

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 Haverhill

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