One of the best tools that you have as gardeners to help us determine 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.

By reviewing the USDA zone info for Houston you should be able to estimate when to plant schizanthus.

Planting Calendar for Schizanthus

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

Schizanthus do not do well in cold weather which means that it is necessary to wait until it warms up after the last frost has passed before you can plant them.

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

Last Frost Date

In Houston the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 20°F.

Just be sure to remember that USDA zone info for Houston is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Houston you get a frost after February 15 so make sure that you are ready to protect your schizanthus if you have one of those late frosts.

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.