The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant trifolium in California should be estimated by referring to the USDA zone info.

Planting Calendar for Trifolium

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

Trifolium tend to make it in mild cold which means that you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant trifolium in California is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant trifolium and expect a good harvest is probably August. Any later than that and your trifolium may not have a chance to fully mature. If you are starting your trifolium indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In California the average date of last frost happens on April 15. You can expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for California is an average the actual date of last frost will vary from year to year. Half of the time in California you get surprised by a frost after April 15 so just be sure to be ready to protect your trifolium in the event of one of those late frosts.

USDA Zone Info for California

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in California

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