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.

You will be able to figure out when it's possible to plant pearl onions by reviewing the USDA zone info for Campbell.

Planting Calendar for Pearl onions

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

You can plant pearl onions slightly earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant pearl onions in Campbell 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 pearl onions and expect a good harvest is probably September. Any later than that and your pearl onions may not have a chance to really do well. Starting your pearl onions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Campbell 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.

It's important to remember that USDA zone info for Campbell is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Campbell you get a frost after February 15 be ready to protect your pearl onions in the event of one of those late frosts.

USDA Zone Info for Campbell

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 Campbell

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