When you think of cacti, you probably envision a vast desert landscape in the American southwest. Maybe there’s tumbleweed blowing by in your imaginary landscape, with the skull of a long-dead cow somewhere in the background. In reality, there are species of cactus that can grow just about anywhere, including the rainy southeastern United States and as far north as the Dakotas.
Prickly pear (Opuntia spp.) cactus is one such species. Adapted to a wide spectrum of temperature ranges, it thrives in the dry, sandy soils of scrubs and sandhills. The species’ tolerance is partially enabled by an “antifreeze chemical” inside its cells, which insulate it from extreme cold. Locally, I’ve seen cacti in the wooded forests of northern Panhandle counties, but most often I encounter the plants on the beach. If you think about it, the sand dunes on our coastal beaches have a lot more in common with deserts than most other waterfront ecosystems. Dunes are extremely sandy and dry, subject to intense heat, and sparsely vegetated. The plants that do grow on dunes are adapted to these conditions, growing deep roots like sea oats, minimal structure like sprawling vines, or tough succulent leaves to keep the salt out and the moisture in.
Succulents like cactus reign supreme over techniques for hoarding water. Because they’re adapted to living in conditions where water sources are few and far between, their modified stems (pads) have specialized open cells called parenchyma, which can hold water for long periods. They also tend to have a mucus layer (think aloe plants) which helps retain water inside the plant.
Prickly pear cacti have earned their very logical name. First, the plant is super prickly. Besides the monster spines covering the whole thing, there are hundreds of nearly invisible, tiny hairlike thorns (called glochids) that will put the inexperienced handler in a world of hurt. In a fascinating twist on drought-tolerant living, the spines are actually modified leaves, which slow down wind that would otherwise evaporate desperately-needed water on the plant.
Secondly, the “pear” part refers to its attractive purple or yellow fruit, which grows right off the pads. Keep in mind, the fruit also contains spiny glochids. The pads and fruit are edible, and full of calcium, fiber, vitamin C, and tons of other nutrients. To harvest them from the wild or in a garden you’ll need to know how to prepare them safely—according to experts from the University of Nevada, burning is one of the easiest ways to remove the glochids. Cleaning them safely is a complicated process. Prickly pear is often sold in local grocery produce sections, so you may just want to purchase them in a store if you’ve never prepped one before.
The plants have large, attractive yellow flowers, which bloom in late spring and attract native pollinators. Mammals and gopher tortoises will also feed on the fruit of the prickly pear. New plants can grow from small pieces of the pads, so they are easy to propagate if you’re interested in using them in a landscape.
On the other hand, these cacti can be a nuisance in a yard or an agricultural setting. In yards, obviously, they can be painful if someone steps on them or an unwitting child or pet gets into them. With livestock, cattle typically avoid the plants due to the thorns, but large patches of cactus can compete with and reduce grazing areas. It can be dug up by the root, but never mowed over—as mentioned before, small pieces will just grow into brand new plants.
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