Secrets to having perennial cacti in the Southeastern United States
Story by Nick Yorlano
Succulents take many forms and come in many shapes and sizes. They are also widely known for their ability to survive in less-than-ideal conditions. Cacti are a type of succulent that is distinguished from other succulents by having areoles. It may seem a little unusual to think of cacti outside of the western United States, however, there are many excellent reasons to grow perennial cacti in the Southeast. First, they are low-maintenance plants: they don’t need supplemental watering as long as they receive normal rainfall within the first 60 days of being planted during the growing season. Once established, they can survive months without a single drop of water. Secondly, most cacti are deer/rabbit resistant. Thirdly, some varieties have flowers as large as 4-6 inches wide that attract butterflies, hummingbirds, and bees. Lastly, there are spineless and some with non-functioning spines.
While most of us do consider cacti native to the arid Southwest, we do actually have native cacti right here – in the good old humid South.
Prickly pear (Opuntia spp.) is a wide-ranging family of cacti with some very impressive winter hardy perennial forms – some have been known to survive temperatures as low as -40 F. There are numerous perennial prickly pear cultivars and mutations. Texas prickly pear (O. engelmannii. var. lindheimeri) is one of the most versatile perennial varieties in the Southeast. This cactus has a wide shrub form that can be trained to grow 4 feet high and wide.
When choosing a site in the landscape, know that they need full sun and well-drained soil – raised beds are great, but if planting inground, make sure the soil is well amended with plenty of organic matter. When planting in pots, cactus pads do better if placed on top of or barely nestled into the soil. A good potting mix for Texas prickly pear is pine fines mixed with 10 percent sand and 10 percent small gravel.
During colder weather, Texas prickly pear will dehydrate, giving them a drooping appearance. Sometimes the cactus pads can break off. The pads will root in during the spring if they are left on the ground next to the plant or replanted in another location. This dehydrating is an adaptive behavior that allows them to survive freezing temperatures.
Tree cholla or cane cholla (Cylindropuntia imbricata) are exceptionally cold hardy perennial cacti well suited for USDA Zones 5-8 in the southeast, but have been known to survive even colder temperatures.
This cactus can obtain a fairly impressive size of 6-8 feet tall and up to 6 feet wide. In their native habitat, tree cholla can reach up to 10 feet tall! Planters or exceptionally well-drained areas, such as rock gardens or raised beds, are excellent places to plant cholla. If growing cholla in planters, use the same soil mixture described above for Texas prickly pear. In landscaping beds, they can adapt to various soil types as long it is well-drained area and in full sun. The most common flower color is magenta, but there are also pink, red, and white forms. Like perennial prickly pear, chollas also dehydrate themselves. They have a shriveled look through the winter months, but quickly break dormancy in the spring.
Beehive cactus (Escobaria vivipara) is a neat variety best suited for troughs or planters. This is a small plant, usually reaching 2-6 inches tall and 8-20 inches wide. There are numerous cultivars, ranging from almost all white spines to almost all black spines. They are best suited for USDA Zones 5-8, but have been known to survive much colder temperatures. When planting in a container, use a very coarse soil such as pine fines with some sand, small gravel, and plenty of organic matter. This cactus also requires full sun. To survive the winter, it will compress itself into a tight little ball.
Claret cup (Echinocereus triglochidiatus) does best in USDA Zones 5-9. Claret cup comes in numerous forms with gorgeous scarlet red flowers. They have a clumping habit and grow anywhere from 1-3, sometimes as much as 12, inches tall and 1-3 feet wide depending on the form.
Lace cactus (Echinocereus reichenbachii) Lace cactus will bloom pink, purple, and magenta. They rarely grow taller than 8-12 inches tall and 2-3 inches wide. When planting in pots use the same soil mixture recommended for the prickly pear. These cacti do very well in planters, troughs, rock gardens, and in the landscape in well-drained soil and full sun. During the winter, Echinocereus compress itself as much as 60 percent in order to survive below-freezing temperatures.
These unique succulents are perfect for modern, xeric, or unorthodox landscaping. They are versatile and available in an almost limitless array of sizes, forms, shapes, and colors.