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

By using the USDA zone info for Rosemead you will be able to estimate when to plant onions.

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 quite a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant onions in Rosemead 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. You probably don't want to wait any later than that or else your onions may not have a chance to fully mature. You can get started a little bit earlier by starting your onions indoors.

Last Frost Date

On average the last frost is on January 31 in Rosemead. In the coldest months of winter you can expect an average low temperature of 30°F.

Just be sure to remember that USDA zone info for Rosemead may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Rosemead you get surprised by a frost after January 31 be ready to cover your onions in the event of a late frost.

USDA Zone Info for Rosemead

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Rosemead

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