One of the best tools that you have as gardeners to help us estimate 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 earliest that you can plant sutera in Zone 4b can be determined by using the USDA zone info.

Planting Calendar for Sutera

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

Sutera do ok in moderate cold which means that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant sutera in Zone 4b 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 sutera and expect a good harvest is probably August. You probably don't want to wait any later than that or else your sutera may not have a chance to fully mature. If you are starting your sutera indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 4b. It might get as low as -25°F during the coldest months of winter.

It's important to remember that USDA zone info for Zone 4b is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 4b you get a frost after May 15 so make sure that you are ready to protect your sutera if you have a surprise late frost.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Zone 4b

You may be interested in your other planting guides for Zone 4b.