One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Zone 1b you will be able to figure out when it's the best time to plant impatiens.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since impatiens are not cold tolerant you have to wait until after the last frost has passed before you can plant them.

The earliest that you can plant impatiens in Zone 1b is June. However, you really should wait until July if you don't want to take any chances.

The last month that you can plant impatiens and expect a good harvest is probably July. If you wait any later than that and your impatiens may not have a chance to fully mature. You can get started a little bit earlier by starting your impatiens indoors.

Last Frost Date

On average the last frost has passed is on June 15 in Zone 1b. You can expect an average low temperature of -55°F in the coldest months of winter.

Always keep in mind that USDA zone info for Zone 1b may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 1b you get surprised by a frost after June 15 so be sure to be ready to protect your impatiens in the event of a late frost.

USDA Zone Info for Zone 1b

Here is the info for USDA Zone 1b.

Average Date of Last Frost (spring)	June 15
Average Date of First Frost (fall)	July 15
Lowest Expected Low	-55°F
Highest Expected Low	-50°F

This means that on a really cold year, the coldest it will get is -55°F. On most years you should be prepared to experience lows near -50°F.

Plants to Grow in Zone 1b

You may be interested in your other planting guides for Zone 1b.