One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when it's a good idea to plant welsh onion in Larkspur by checking out the USDA zone info.

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.

Welsh onion are one of those plants that can tolerate a tiny bit of cold weather which means that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant welsh onion in Larkspur 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 fully mature. If you are starting your welsh onion indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Larkspur. In the coldest months of winter you can expect an average low temperature of 25°F.

Always keep in mind that USDA zone info for Larkspur is an average and the actual date of last frost will vary from year to year. Half of the time in Larkspur it frosts late in the year after February 15 so always be ready to cover your welsh onion if you have a surprise late frost.

USDA Zone Info for Larkspur

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 Larkspur

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