One of the best tools that you have as gardeners to help us estimate 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.

The USDA zone info for Harlingen can be reviewed to estimate when to plant calibrachoa.

Planting Calendar for Calibrachoa

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

Calibrachoa do ok in moderate cold which means that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant calibrachoa in Harlingen 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 calibrachoa and expect a good harvest is probably September. If you wait any later than that and your calibrachoa may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your calibrachoa indoors.

Last Frost Date

In Harlingen the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Harlingen and it changes from year to year. Half of the time in Harlingen last frost occurs after February 15 so make sure that you are ready to cover your calibrachoa in the event of one of those late frosts.

USDA Zone Info for Harlingen

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Harlingen

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