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.

A common way of estimating when it's possible to plant welsh onion is to consult the USDA zone info for Longwood.

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 do ok in moderate cold you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant welsh onion in Longwood 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. If you wait any later than that and your welsh onion may not have a chance to really do well. You can get started a little bit earlier by starting your welsh onion indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Longwood. It might get as low as 25°F during the coldest months of winter.

Remember that USDA zone info for Longwood 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 Longwood last frost occurs after February 15 be ready to cover your welsh onion if you have a late frost.

USDA Zone Info for Longwood

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 Longwood

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