The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when it's the best time to plant onions by using the USDA zone info for Morro Bay.

Planting Calendar for Onions

Frost tolerance for onions:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Onions are one of those plants that can tolerate quite a bit of cold weather which means that you can plant them much earlier than other frost tender plants.

The earliest that you can plant onions in Morro Bay is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant onions and expect a good harvest is probably October. If you wait any later than that and your onions may not have a chance to grow to maturity. You can get started a little bit earlier by starting your onions indoors.

Last Frost Date

In Morro Bay 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.

Just be sure to remember that USDA zone info for Morro Bay 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 Morro Bay you get a frost after February 15 be ready to protect your onions if you have a surprise late frost.

USDA Zone Info for Morro Bay

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 Morro Bay

You may be interested in your other planting guides for Morro Bay.