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.

It's possible to determine when you can plant tree onions by referring to the USDA zone info for Scotts Valley.

Planting Calendar for Tree onions

Frost tolerance for tree onions:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since tree onions are barely cold tolerant 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 tree onions in Scotts Valley 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 tree onions and expect a good harvest is probably September. You probably don't want to wait any later than that or else your tree onions may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your tree onions indoors.

Last Frost Date

The average date of last frost is February 15 in Scotts Valley. 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 Scotts Valley and it changes from year to year. Since half of the time in Scotts Valley last frost occurs after February 15 be ready to cover your tree onions if you have a late frost.

USDA Zone Info for Scotts Valley

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 Scotts Valley

You may be interested in your other planting guides for Scotts Valley.