One of the first steps you take when you are figuring out 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 estimate when you can plant welsh onion by referring to the USDA zone info for Chula Vista.

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 can survive in very little cold which means that you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant welsh onion in Chula Vista 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. If you wait any later than that and your welsh onion may not have a chance to really do well. You can get started a couple of weeks earlier by starting your welsh onion indoors.

Last Frost Date

The average date of last frost is January 31 in Chula Vista. You can expect an average low temperature of 35°F in the coldest months of winter.

Remember that USDA zone info for Chula Vista is just an average and the actual date of last frost is different every year. Half of the time in Chula Vista you get a frost after January 31 so make sure that you are prepared to cover your welsh onion if you have one of those late frosts.

USDA Zone Info for Chula Vista

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Chula Vista

You may be interested in your other planting guides for Chula Vista.