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.

By checking out the USDA zone info for Rio Vista you should be able to figure out when it's a good idea to plant lisianthus.

Planting Calendar for Lisianthus

Frost tolerance for lisianthus:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Lisianthus are not cold tolerant which tells us that it's important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant lisianthus in Rio Vista 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 lisianthus and expect a good harvest is probably September. You probably don't want to wait any later than that or else your lisianthus may not have a chance to fully mature. Starting your lisianthus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Rio Vista. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Rio Vista may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Rio Vista it frosts late in the year after February 15 be ready to protect your lisianthus in the event of one of those late frosts.

USDA Zone Info for Rio Vista

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 Rio Vista

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