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.

One way of figuring out when it's a good idea to plant bells of ireland is to use the USDA zone info for San Bruno.

Planting Calendar for Bells of Ireland

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

You can plant bells of ireland just a tiny bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant bells of ireland 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 bells of ireland and expect a good harvest is probably September. You probably don't want to wait any later than that or else your bells of ireland may not have a chance to fully mature. If you are starting your bells of ireland indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on January 31 in San Bruno. You can expect an average low temperature of 30°F in the coldest months of winter.

It's important to remember that USDA zone info for San Bruno is not always accurate and the actual date of last frost will vary from year to year. Half of the time in San Bruno there is a last frost after January 31 so make sure that you are prepared to cover your bells of ireland in the event of a 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.