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.

The USDA zone info for Hercules can be used to determine when to plant trifolium.

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 means that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant trifolium in Hercules 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 grow to maturity. Starting your trifolium indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Hercules. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Hercules is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Hercules it frosts late in the year after February 15 so make sure that you are prepared to protect your trifolium if you have one of those late frosts.

USDA Zone Info for Hercules

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 Hercules

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