One of the best tools that you have as gardeners to help us determine 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.

By using the USDA zone info for Petaluma you will be able to figure out when to plant armeria.

Planting Calendar for Armeria

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

Armeria tend to make it in pretty solid cold which tells us that you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant armeria in Petaluma 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 armeria and expect a good harvest is probably October. Any later than that and your armeria may not have a chance to fully mature. If you are starting your armeria indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Petaluma. You should expect an average low temperature of 25°F in the coldest months of winter.

Remember that USDA zone info for Petaluma is not always accurate and the actual date of last frost changes from year to year. Half of the time in Petaluma there is a last frost after February 15 so be sure to be ready to cover your armeria if you have one of those late frosts.

USDA Zone Info for Petaluma

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 Petaluma

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