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.

You can figure out when it's the best time to plant sweet potatos in Ukiah by using the USDA zone info.

Planting Calendar for Sweet Potatos

Frost tolerance for sweet potatos:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's not a good idea to plant sweet potatos until after the last frost because they require warm weather.

The earliest that you can plant sweet potatos in Ukiah is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant sweet potatos and expect a good harvest is probably September. Any later than that and your sweet potatos may not have a chance to grow to maturity. If you are starting your sweet potatos indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Ukiah. In the coldest months of winter you can expect an average low temperature of 20°F.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Ukiah and it is different every year. Half of the time in Ukiah you get a frost after February 15 so be sure to be ready to cover your sweet potatos in the event of a late frost.

USDA Zone Info for Ukiah

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Ukiah

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