One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

The first opportunity to plant four o' clock in Haverhill can be figured out by reviewing the USDA zone info.

Planting Calendar for Four O' Clock

Frost tolerance for four o' clock:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since four o' clock do not do well in cold weather it is necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant four o' clock in Haverhill 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 four o' clock and expect a good harvest is probably August. Any later than that and your four o' clock may not have a chance to grow to maturity. Starting your four o' clock 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 Haverhill. In the coldest months of winter you can expect an average low temperature of -10°F.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Haverhill and it changes from year to year. Since half of the time in Haverhill there is a last frost after April 15 be ready to cover your four o' clock in the event of a surprise late frost.

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.