When to Plant Onions in Morgan Hill, 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.

You will be able to figure out when to plant onions by using the USDA zone info for Morgan Hill.


Planting Calendar for Onions

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

You can plant onions much earlier in the year because they are very cold tolerant.

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

The earliest that you can plant onions in Morgan Hill 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. Any later than that and your onions may not have a chance to really do well. If you are starting your onions indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Morgan Hill the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Always keep in mind that USDA zone info for Morgan Hill is an average and the actual date of last frost is different every year. Half of the time in Morgan Hill there is a last frost after February 15 so always be ready to cover your onions if you have a late frost.

USDA Zone Info for Morgan Hill

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 Morgan Hill

You may be interested in your other planting guides for Morgan Hill.