One of the best tools that you have as gardeners to help us figure out 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 USDA zone info for Riverside should be looked at to estimate when to plant oxalis.

Planting Calendar for Oxalis

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

Since oxalis require warm weather you really should wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant oxalis in Riverside 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 oxalis and expect a good harvest is probably August. If you wait any later than that and your oxalis may not have a chance to fully mature. If you are starting your oxalis indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Riverside the average date of last frost happens on April 15. You should expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Riverside and it changes from year to year. Since half of the time in Riverside you get surprised by a frost after April 15 be ready to protect your oxalis if you have a surprise late frost.

USDA Zone Info for Riverside

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Riverside

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