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

One way of making a decision about when it's possible to plant hibiscus is to consult the USDA zone info for Petaluma.

Planting Calendar for Hibiscus

Frost tolerance for hibiscus:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Hibiscus do not do well in cold weather which means that you must wait until it warms up after the last frost has passed before you can plant them.

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

Last Frost Date

In Petaluma the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Petaluma and it is different every year. Since half of the time in Petaluma last frost occurs after February 15 be ready to cover your hibiscus if you have a surprise late frost.

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.