One of the first steps you take when you are figuring out 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.

In San Bruno you can estimate when it's possible to plant nierembergia by looking at the USDA zone info.

Planting Calendar for Nierembergia

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

Since nierembergia are not cold tolerant you have to wait until after the last frost has passed before you can plant them.

The earliest that you can plant nierembergia in San Bruno 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. If you wait any later than that and your nierembergia may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your nierembergia indoors.

Last Frost Date

The average date of last frost is January 31 in San Bruno. It might get as low as 30°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for San Bruno and it is different every year. Since half of the time in San Bruno there is a last frost after January 31 be ready to cover your nierembergia in the event of a surprise late frost.

USDA Zone Info for San Bruno

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 Bruno

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