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.

A way of making a decision about when you can plant trifolium is to use the USDA zone info for Winters.

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 are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant trifolium in Winters 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. You probably don't want to wait any later than that or else your trifolium may not have a chance to fully mature. Starting your trifolium indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Winters the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Winters is not always accurate the actual date of last frost changes from year to year. Since half of the time in Winters it frosts late in the year after February 15 be ready to cover your trifolium in the event of a late frost.

USDA Zone Info for Winters

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 Winters

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