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.

A way of figuring out when to plant saxifraga is to consult the USDA zone info for Tomball.

Planting Calendar for Saxifraga

Frost tolerance for saxifraga:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant saxifraga slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant saxifraga in Tomball is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant saxifraga and expect a good harvest is probably September. Any later than that and your saxifraga may not have a chance to really do well. If you are starting your saxifraga indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Tomball. You can expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Tomball is not always accurate the actual date of last frost will vary from year to year. Half of the time in Tomball last frost occurs after February 15 so just be sure to be ready to protect your saxifraga if you have a surprise late frost.

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.