When to Plant Onions in Menlo Park, CA

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when to plant onions in Menlo Park by using the USDA zone info.


Planting Calendar for Onions

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

Since onions do well in cold you can plant them earlier in the year than more sensitive plants.

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 Menlo Park 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. Starting your onions indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Menlo Park may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Menlo Park it frosts late in the year after February 15 be ready to protect your onions if you have one of those late frosts.

USDA Zone Info for Menlo Park

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 Menlo Park

You may be interested in your other planting guides for Menlo Park.