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.

In Lathrop you can determine when you can plant bunching onions 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.

Bunching Onions are one of those plants that can tolerate a tiny bit of cold weather which means that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant bunching onions in Lathrop 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. You probably don't want to wait any later than that or else your bunching onions may not have a chance to grow to maturity. If you are starting your bunching onions indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Lathrop the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Lathrop is an average the actual date of last frost is different every year. Half of the time in Lathrop you get surprised by a frost after February 15 so always be ready to protect your bunching onions if you have a surprise late frost.

USDA Zone Info for Lathrop

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 Lathrop

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