The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's possible to plant sunflowers in Humble by looking at the USDA zone info.

Planting Calendar for Sunflowers

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

It's probably not a good idea to plant sunflowers until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant sunflowers 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 sunflowers and expect a good harvest is probably September. You probably don't want to wait any later than that or else your sunflowers may not have a chance to fully mature. You can get started a little bit earlier by starting your sunflowers indoors.

Last Frost Date

On average all chance of frost has passed is on February 15 in Humble. 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 Humble is an average and the actual date of last frost changes from year to year. Half of the time in Humble you get a frost after February 15 so make sure that you are prepared to cover your sunflowers in the event of a surprise 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.