First impressions are critical when selling a home, and I give credit to the former owners of our house for choosing a rather unique mailbox post. Instead of a traditional post designed to support a mailbox and perhaps a newspaper holder, this white PVC design also incorporated a planter. As a plant enthusiast, the planter feature was instantly appealing.
After my first summer, I quickly learned that the mailbox container’s tiny planting space would be challenging. Sweltering summer temperatures combined with the small volume of the container caused the soil to dry out very rapidly. I simply couldn’t keep up with the water needs of most of my go-to container plants.
It was evident that I would need plant material that was drought tolerant, but what would provide that pop of color and flourish in a rather harsh environment? A succulent! Succulents are plants with thick fleshy tissues adapted for water storage. Most people are familiar with cacti, and while members of the cactus family are succulents, there are many non-cactus succulents from other plant families.
After some brainstorming, I settled on purslane (Portulaca oleracea), which thrives in hot, dry conditions. Its groundcover-type habit makes it perfect for this setting in which the showy flowers drape pendulously over the edge of the container. The flowers close at night and on cloudy days, a fascinating behavior known as nyctinasty. With an assortment of flower colors, including some that are spotted or striped, you’re sure to find a purslane that compliments your design needs.
When it comes to care, purslane is a minimalist requiring just occasional water when the soil dries out. No pruning or deadheading is needed, although you may wish to prune seedpods to prevent new plants from popping up in unwanted areas of your landscape.
For additional ideas on plant species that might perform well in a small container such as a mailbox planter, refer to the section “Annuals for Hot, Dry Locations” in HGIC 1152, Growing Annuals.