One of the first steps you take when you are estimating your gardening schedule is find your 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.

The earliest that you can plant asters in Tomball should be determined by using the USDA zone info.

Planting Calendar for Asters

Frost tolerance for asters:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Asters do well in moderate cold which tells us that you can get them planted earlier than plants that are more sensitive to the cold.

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

The last month that you can plant asters and expect a good harvest is probably October. If you wait any later than that and your asters may not have a chance to fully mature. Starting your asters indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Tomball is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Tomball last frost occurs after February 15 so make sure that you are prepared to protect your asters if you have a 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.