Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of getting a good idea when it's a good idea to plant welsh onion is to refer to the USDA zone info for Inverness.

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 just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant welsh onion in Inverness 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. If you are starting your welsh onion indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Inverness. It might get as low as 20°F during the coldest months of winter.

It's important to remember that USDA zone info for Inverness is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Inverness it frosts late in the year after February 15 so make sure that you are prepared to cover your welsh onion in the event of one of those late frosts.

USDA Zone Info for Inverness

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Inverness

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