One of the first steps you take when you are figuring out your gardening schedule is find your 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.

By reviewing the USDA zone info for Andover it's a good idea to estimate when it's a good idea to plant nierembergia.

Planting Calendar for Nierembergia

Frost tolerance for nierembergia:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You can not plant nierembergia until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant nierembergia in Andover is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant nierembergia and expect a good harvest is probably August. If you wait any later than that and your nierembergia may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your nierembergia indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Andover. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Andover is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Andover last frost occurs after May 15 so make sure that you are prepared to cover your nierembergia in the event of a surprise late frost.

USDA Zone Info for Andover

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 Andover

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