One of the first steps you take when you are figuring out 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.

It's a good idea to estimate when you can plant hollyhocks by looking at the USDA zone info for Tomball.

Planting Calendar for Hollyhocks

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

Hollyhocks can survive in moderate cold which means that you can plant them a little earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant hollyhocks 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 hollyhocks and expect a good harvest is probably October. If you wait any later than that and your hollyhocks may not have a chance to grow to maturity. If you are starting your hollyhocks 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. It might get as low as 20°F during the coldest months of winter.

Keep in mind that USDA zone info for Tomball is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Tomball you get a frost after February 15 so make sure that you are prepared to cover your hollyhocks 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.