Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Waltham you can estimate when it's the best time to plant iresene by checking out the USDA zone info.

Planting Calendar for Iresene

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

Iresene do not do well in cold weather which means that you really should wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant iresene 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 iresene and expect a good harvest is probably August. Any later than that and your iresene may not have a chance to grow to maturity. Starting your iresene indoors is a great way to get them started a few weeks 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 may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Waltham there is a last frost after April 15 so make sure that you are prepared to protect your iresene if you have 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.