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.

The USDA zone info for Berkeley should be reffered to in order to figure out when to plant welsh onion.

Planting Calendar for Welsh onion

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

Welsh onion do ok in very little cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant welsh onion in Berkeley 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 welsh onion and expect a good harvest is probably September. Any later than that and your welsh onion may not have a chance to fully mature. Starting your welsh onion indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Berkeley is just an average the actual date of last frost is different every year. Since half of the time in Berkeley you get a frost after January 31 be ready to cover your welsh onion in the event of a surprise late frost.

USDA Zone Info for Berkeley

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 Berkeley

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