One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of figuring out when it's a good idea to plant nierembergia is to refer to the USDA zone info for Yuba City.

Planting Calendar for Nierembergia

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

Nierembergia do not do well in cold weather which tells us that it's necessary to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant nierembergia in Yuba City 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 nierembergia and expect a good harvest is probably September. Any later than that and your nierembergia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your nierembergia indoors.

Last Frost Date

The average date of last frost is February 15 in Yuba City. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Yuba City may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Yuba City it frosts late in the year after February 15 be ready to cover your nierembergia if you have a late frost.

USDA Zone Info for Yuba City

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 Yuba City

You may be interested in your other planting guides for Yuba City.