Before planting it is a good idea to find your USDA Zone info to determine 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.

The earliest that you can plant bunching onions in Imperial should be determined by referring to the USDA zone info.

Planting Calendar for Bunching Onions

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

You can plant bunching onions just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant bunching onions in Imperial 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 bunching onions and expect a good harvest is probably September. Any later than that and your bunching onions may not have a chance to grow to maturity. Starting your bunching onions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Imperial the average date of last frost happens on January 31. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Imperial is an average the actual date of last frost will vary from year to year. Half of the time in Imperial you get a frost after January 31 so make sure that you are ready to cover your bunching onions in the event of one of those late frosts.

USDA Zone Info for Imperial

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Imperial

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