The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of estimating when it's a good idea to plant lemon balm is to look at the USDA zone info for South Houston.

Planting Calendar for Lemon balm

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

Since lemon balm are barely cold tolerant you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant lemon balm in South Houston 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 lemon balm and expect a good harvest is probably September. Any later than that and your lemon balm may not have a chance to fully mature. Starting your lemon balm indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In South Houston the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 20°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for South Houston and it is different every year. Half of the time in South Houston last frost occurs after February 15 so just be sure to be ready to cover your lemon balm if you have a late frost.

USDA Zone Info for South Houston

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 South Houston

You may be interested in your other planting guides for South Houston.