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.

You can figure out when it's possible to plant lisianthus in Houston by referring to the USDA zone info.

Planting Calendar for Lisianthus

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

Lisianthus do not do well in cold weather which means that you must wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant lisianthus in Houston 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 few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Houston. It might get as low as 20°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Houston and it is different every year. Since half of the time in Houston there is a last frost after February 15 be ready to cover your lisianthus if you have a surprise late frost.

USDA Zone Info for Houston

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 Houston

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