One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of figuring out when it's the best time to plant lisianthus is to examine the USDA zone info for Zone 9b.

Planting Calendar for Lisianthus

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

Since lisianthus require warm weather it is necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant lisianthus in Zone 9b 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. If you are starting your lisianthus indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Zone 9b. In the coldest months of winter you can expect an average low temperature of 25°F.

Keep in mind that USDA zone info for Zone 9b may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Zone 9b there is a last frost after February 15 be ready to cover your lisianthus in the event of one of those late frosts.

USDA Zone Info for Zone 9b

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 Zone 9b

You may be interested in your other planting guides for Zone 9b.