The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Mill Valley it's possible to figure out when to plant pearl onions.

Planting Calendar for Pearl onions

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

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

The earliest that you can plant pearl onions 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 pearl onions and expect a good harvest is probably September. Any later than that and your pearl onions may not have a chance to fully mature. If you are starting your pearl onions indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Mill Valley the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for Mill Valley is just an average the actual date of last frost changes from year to year. Since half of the time in Mill Valley there is a last frost after January 31 be ready to protect your pearl onions 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.