One of the first steps you take when you are determining your gardening schedule is find your 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.

By looking at the USDA zone info for Mill Valley you should be able to estimate when it's a good idea to plant rosemary.

Planting Calendar for Rosemary

Frost tolerance for rosemary:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since rosemary are very cold tolerant you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant rosemary in Mill Valley is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant rosemary and expect a good harvest is probably October. Any later than that and your rosemary may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your rosemary indoors.

Last Frost Date

On average the last frost has passed is on January 31 in Mill Valley. It might get as low as 30°F during the coldest months of winter.

Always keep in mind that USDA zone info for Mill Valley may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Mill Valley you get a frost after January 31 be ready to cover your rosemary if you have 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.