If you've ever wondered why Harris County residents celebrate Arbor Day multiple times a year, you're not alone.

Although National Arbor Day is always celebrated on the last Friday in April, many counties and states observe Arbor Day on different dates throughout the year, based on the best tree planting times for their region.

Harris County residents celebrate Texas Arbor Day on the first Friday in November and Houston Arbor Day in late January. Like many southerners, Texans celebrate Arbor Day in autumn and winter to allow the tree time to establish a healthy root system before summer. Because of Houston's subtropical climate and mild winters, arborists consider late January a prime time to plant trees. By then, many trees are still dormant, and warmer weather is only a few months away.

As a resident of Harris County, rejoice in knowing that you get to celebrate this beneficial holiday three times a year. With Texas' long growing season, there's really no reason to slow your tree planting.