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

It's a good idea to determine when to plant violas by using the USDA zone info for Riverside.

Planting Calendar for Violas

Frost tolerance for violas:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant violas much earlier in the year because they do well in cold.

The earliest that you can plant violas in Riverside 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 violas and expect a good harvest is probably September. If you wait any later than that and your violas may not have a chance to grow to maturity. If you are starting your violas 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.

Since the USDA zone info for Riverside may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Riverside you get a frost after April 15 so just be sure to be ready to protect your violas if you have one of those late frosts.

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.