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

By reviewing the USDA zone info for Mendota it's a good idea to estimate 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.

Since welsh onion are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant welsh onion in Mendota 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. Any later than that and your welsh onion may not have a chance to grow to maturity. Starting your welsh onion indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Mendota 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.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Mendota and it will vary from year to year. Half of the time in Mendota you get a frost after February 15 so just be sure to be ready to protect your welsh onion if you have a surprise late frost.

USDA Zone Info for Mendota

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 Mendota

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