The USDA Zone info is a great tool for gardeners to help us determine your gardening 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 estimating when it's a good idea to plant trachelium is to use the USDA zone info for Colusa.

Planting Calendar for Trachelium

Frost tolerance for trachelium:	Not tolerant of frost.
When to plant:	After the last frost.

Trachelium require warm weather which means that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant trachelium in Colusa 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 trachelium and expect a good harvest is probably September. You probably don't want to wait any later than that or else your trachelium may not have a chance to grow to maturity. You can get started a little bit earlier by starting your trachelium indoors.

Last Frost Date

On average all chance of frost has passed is on February 15 in Colusa. It might get as low as 25°F during the coldest months of winter.

Keep in mind that USDA zone info for Colusa is an average and the actual date of last frost is different every year. Half of the time in Colusa last frost occurs after February 15 so make sure that you are ready to protect your trachelium if you have a late frost.

USDA Zone Info for Colusa

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 Colusa

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