One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when it's a good idea to plant bunching onions by reviewing the USDA zone info for Manteca.

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 do ok in some cold which means that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant bunching onions in Manteca 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. If you wait 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 Manteca 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 Manteca may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Manteca it frosts late in the year after February 15 so be sure to be ready to protect your bunching onions if you have a late frost.

USDA Zone Info for Manteca

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 Manteca

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