One of the best tools that you have as gardeners to help us estimate 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 reviewing the USDA zone info for Las Vegas you will be able to figure out when you can plant alternanthera.

Planting Calendar for Alternanthera

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

It's probably not a good idea to plant alternanthera until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant alternanthera in Las Vegas is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant alternanthera and expect a good harvest is probably September. If you wait any later than that and your alternanthera may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your alternanthera indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Las Vegas. In the coldest months of winter you should expect an average low temperature of 20°F.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Las Vegas and it is different every year. Half of the time in Las Vegas there is a last frost after February 15 so make sure that you are ready to protect your alternanthera in the event of a surprise late frost.

USDA Zone Info for Las Vegas

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

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

Plants to Grow in Las Vegas

You may be interested in your other planting guides for Las Vegas.