The USDA Zone info is a great tool for gardeners to help us estimate 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 calibrachoa in Mill Valley should be figured out by using the USDA zone info.

Planting Calendar for Calibrachoa

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

You can plant calibrachoa just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant calibrachoa in Mill Valley 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 calibrachoa and expect a good harvest is probably September. Any later than that and your calibrachoa may not have a chance to really do well. If you are starting your calibrachoa indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in Mill Valley. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Mill Valley is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Mill Valley it frosts late in the year after January 31 so make sure that you are ready to cover your calibrachoa in the event of one of those late frosts.

USDA Zone Info for Mill Valley

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Mill Valley

You may be interested in your other planting guides for Mill Valley.