Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when it's possible to plant alternanthera is to use the USDA zone info for Rock Falls.

Planting Calendar for Alternanthera

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

Since alternanthera require warm weather you need to wait until after the last frost before you can plant them.

The earliest that you can plant alternanthera in Rock Falls 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 alternanthera and expect a good harvest is probably August. If you wait any later than that and your alternanthera may not have a chance to fully mature. Starting your alternanthera indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Rock Falls. It might get as low as -15°F during the coldest months of winter.

Remember that USDA zone info for Rock Falls may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Rock Falls you get a frost after April 15 so always be ready to cover your alternanthera in the event of a surprise late frost.

USDA Zone Info for Rock Falls

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Rock Falls

You may be interested in your other planting guides for Rock Falls.