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.

By looking at the USDA zone info for San Rafael you will be able to estimate when you can plant nierembergia.

Planting Calendar for Nierembergia

Frost tolerance for nierembergia:	Not tolerant of frost.
When to plant:	After the last frost.

Since nierembergia do not do well in cold weather you really should wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant nierembergia in San Rafael 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 nierembergia and expect a good harvest is probably September. Any later than that and your nierembergia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your nierembergia indoors.

Last Frost Date

The average date of last frost is January 31 in San Rafael. In the coldest months of winter you can expect an average low temperature of 30°F.

Always keep in mind that USDA zone info for San Rafael is an average and the actual date of last frost is different every year. Since half of the time in San Rafael it frosts late in the year after January 31 be ready to protect your nierembergia in the event of one of those late frosts.

USDA Zone Info for San Rafael

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 San Rafael

You may be interested in your other planting guides for San Rafael.