Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of getting a good idea when to plant lisianthus is to examine the USDA zone info for Rialto.

Planting Calendar for Lisianthus

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

It's probably a bad idea to plant lisianthus until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant lisianthus in Rialto is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant lisianthus and expect a good harvest is probably September. Any later than that and your lisianthus may not have a chance to really do well. Starting your lisianthus 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 January 31 in Rialto. You can expect an average low temperature of 30°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Rialto and it will vary from year to year. Since half of the time in Rialto last frost occurs after January 31 be ready to cover your lisianthus if you have a late frost.

USDA Zone Info for Rialto

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Rialto

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