One of the first steps you take when you are determining your gardening schedule is find your 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.

You will be able to figure out when you can plant alternaria by checking out the USDA zone info for Rialto.

Planting Calendar for Alternaria

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

Alternaria require warm weather which tells us that you have to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant alternaria 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 alternaria and expect a good harvest is probably September. You probably don't want to wait any later than that or else your alternaria may not have a chance to really do well. Starting your alternaria indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Rialto the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Rialto is an average the actual date of last frost will vary from year to year. Since half of the time in Rialto last frost occurs after January 31 be ready to cover your alternaria in the event of a surprise 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.