Before planting it is a good idea to find your USDA Zone info to determine 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.

By referring to the USDA zone info for Rialto it's a good idea to estimate when to plant bittercress.

Planting Calendar for Bittercress

Frost tolerance for bittercress:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant bittercress slightly earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant bittercress 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 bittercress and expect a good harvest is probably September. Any later than that and your bittercress may not have a chance to fully mature. You can get started a little bit earlier by starting your bittercress indoors.

Last Frost Date

On average the last frost is on January 31 in Rialto. In the coldest months of winter you can expect an average low temperature of 30°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Rialto and it is different every year. Since half of the time in Rialto you get a frost after January 31 be ready to cover your bittercress in the event of one of those late frosts.

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.