One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant mimulus in Rialto should be estimated by using the USDA zone info.

Planting Calendar for Mimulus

Frost tolerance for mimulus:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's probably a bad idea to plant mimulus until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant mimulus 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 mimulus and expect a good harvest is probably September. If you wait any later than that and your mimulus may not have a chance to really do well. If you are starting your mimulus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Rialto. In the coldest months of winter you should expect an average low temperature of 30°F.

Remember that USDA zone info for Rialto is just an average and the actual date of last frost will vary from year to year. Half of the time in Rialto you get a frost after January 31 so make sure that you are prepared to cover your mimulus 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.