One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Rialto it's possible to estimate when you can plant scabiosa.

Planting Calendar for Scabiosa

Frost tolerance for scabiosa:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Scabiosa are one of those plants that can tolerate a little bit of cold weather which means that you can plant them a little bit earlier than more sensitive plants.

The earliest that you can plant scabiosa in Rialto is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant scabiosa and expect a good harvest is probably October. Any later than that and your scabiosa may not have a chance to grow to maturity. Starting your scabiosa indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Rialto. It might get as low as 30°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Rialto is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Rialto there is a last frost after January 31 be ready to protect your scabiosa if you have 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.