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 way of getting a good idea when it's possible to plant nasturtium is to consult the USDA zone info for Tomball.

Planting Calendar for Nasturtium

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

Since nasturtium require warm weather you have to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant nasturtium in Tomball 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 nasturtium and expect a good harvest is probably September. You probably don't want to wait any later than that or else your nasturtium may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your nasturtium indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Tomball. In the coldest months of winter you should expect an average low temperature of 20°F.

Since the USDA zone info for Tomball is an average the actual date of last frost changes from year to year. Since half of the time in Tomball you get a frost after February 15 be ready to cover your nasturtium if you have one of those late frosts.

USDA Zone Info for Tomball

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 Tomball

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