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

The earliest that you can plant catharanthus in Humble can be estimated by looking at the USDA zone info.

Planting Calendar for Catharanthus

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

Since catharanthus require warm weather it's important to wait until after the last frost before you can plant them.

The earliest that you can plant catharanthus in Humble 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 catharanthus and expect a good harvest is probably September. If you wait any later than that and your catharanthus may not have a chance to really do well. Starting your catharanthus indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Humble. In the coldest months of winter you should expect an average low temperature of 20°F.

Since the USDA zone info for Humble is not always accurate the actual date of last frost changes from year to year. Half of the time in Humble there is a last frost after February 15 so always be ready to cover your catharanthus if you have a late frost.

USDA Zone Info for Humble

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 Humble

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