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.

The first chance to plant alternanthera in Superior should be figured out by reviewing the USDA zone info.

Planting Calendar for Alternanthera

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

It's probably a bad idea to plant alternanthera until after the last frost has passed because they require warm weather.

The earliest that you can plant alternanthera in Superior 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 alternanthera and expect a good harvest is probably August. Any later than that and your alternanthera may not have a chance to really do well. You can get started a couple of weeks earlier by starting your alternanthera indoors.

Last Frost Date

On average the last frost is on May 15 in Superior. It might get as low as -25°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Superior and it can change quite a bit from year to year. Half of the time in Superior you get a frost after May 15 so always be ready to cover your alternanthera if you have one of those late frosts.

USDA Zone Info for Superior

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 Superior

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