The USDA Zone info is a great tool for gardeners to help us determine 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.

It's possible to estimate when it's the best time to plant welsh onion by referring to the USDA zone info for Windsor.

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.

You can plant welsh onion a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant welsh onion in Windsor 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. You probably don't want to wait any later than that or else your welsh onion may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your welsh onion indoors.

Last Frost Date

In Windsor 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 USDA zone info for Windsor is an average and the actual date of last frost will vary from year to year. Since half of the time in Windsor you get surprised by a frost after February 15 be ready to cover your welsh onion in the event of a surprise late frost.

USDA Zone Info for Windsor

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 Windsor

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