Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Orinda you can determine when it's the best time to plant welsh onion by reviewing the USDA zone info.

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.

Since welsh onion do ok in moderate cold you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant welsh onion in Orinda 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 really do well. You can get started a few weeks earlier by starting your welsh onion indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Orinda. It might get as low as 25°F during the coldest months of winter.

Keep in mind that USDA zone info for Orinda is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Orinda you get a frost after February 15 be ready to cover your welsh onion if you have a surprise late frost.

USDA Zone Info for Orinda

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 Orinda

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