The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

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

Planting Calendar for Alternanthera

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

You should not plant alternanthera until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant alternanthera in Key West is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant alternanthera and expect a good harvest is probably November. Any later than that and your alternanthera may not have a chance to grow to maturity. Starting your alternanthera indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Key West it never frosts. It might get as low as 45°F during the coldest months of winter.

Since the USDA zone info for Key West is an average the actual date of last frost is different every year. Since it never frosts in Key West you do not have to be ready to protect your alternanthera if you have a late frost.

USDA Zone Info for Key West

Here is the info for USDA Zone 11b.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	45°F
Highest Expected Low	50°F

This means that on a really cold year, the coldest it will get is 45°F. On most years you should be prepared to experience lows near 50°F.

Plants to Grow in Key West

You may be interested in your other planting guides for Key West.