One of the best tools that you have as gardeners to help us determine 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 best time to plant trifolium in Orinda can be figured out 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 do ok in moderate cold which means that you can start planting them slightly earlier than other plants that might not handle the cold.

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

Last Frost Date

In Orinda the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Orinda is not always accurate the actual date of last frost changes from year to year. Half of the time in Orinda there is a last frost after February 15 so make sure that you are prepared to cover your trifolium if you have a surprise late frost.

USDA Zone Info for Orinda

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Orinda

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