When to Plant Welsh onion in Walnut Creek, CA

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for Walnut Creek you will be able to figure out when it's the best time 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 well in some cold which tells us that you can plant them slightly earlier in the year than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant welsh onion
Possibly ok, but a risky time to plant welsh onion
Probably not a good time to plant welsh onion

The earliest that you can plant welsh onion in Walnut Creek 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. If you wait 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

In Walnut Creek the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Walnut Creek and it changes from year to year. Since half of the time in Walnut Creek you get a frost after February 15 be ready to cover your welsh onion in the event of a surprise late frost.

USDA Zone Info for Walnut Creek

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 Low25°F
Highest Expected Low30°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 Walnut Creek

You may be interested in your other planting guides for Walnut Creek.