by Ken Lain, the mountain gardener
A chill is in the air, so the furnace or fireplace has been back to its warming work. This is a trying time of transition for many houseplants because the heated air causes the humidity in your home to drop.
Luckily, this isn’t a problem for cactuses as these desert plants appreciate dry air and average room temperatures. Although cactuses like at least three hours of sun per day, I always am surprised how robustly cacti can exist in rooms without a window! A happy cactus may even surprise you with vibrant blooms, a bonus from a plant that already shows off with abstract shapes and spiny textures. The slow growth and easy care requirements of any cacti make for rewarding houseplants. They are suitable additions to mixed container plantings and make fine standalone specimens. Here are my top eight picks from the varieties of cacti most popular to local gardeners:
Angel Wings Cactus, Opuntia albispina, is a member of the prickly pear family, but rather than sharp spines it grows evenly spaced clumps of hairs. This Mexican native produces clusters of pads that get no more substantial than two feet tall but over time can grow up to five feet across. If this cactus grows too large, simply slice back pads to the desired size. In spring, pale yellow flowers are followed by red, edible fruits.
African Milk Tree, Euphorbia trigona, is one of those plants that make every gardener feel like a pro. This is a slow grower and indoors it is unlikely to grow much past four feet high. Small green leaves grow between thorns on the ridged stems, and if you find the Rubra variety, the leaves are reddish-purple. Planted in good quality cactus potting soil and watered twice a month an African milk tree will live for decades.
Barrel Cactus, Ferocactus, got its name from its shape. The juicy, edible pulp is covered with stunning spines. Barrel cactuses may live for many decades, and when grown in the Arizona desert eventually can reach a maximum height of 8 feet. As a houseplant in an appropriate cactus potting mix, a barrel cactus craves as much sun as possible, and limited irrigation.
Bishop’s Cap, Astrophytum ornatum, looks striking in a substantial ceramic pot mulched with decorative gravel. Stiff spikes cover deeply ridged spheres, which can grow to several feet in height. The plants often develop a frosty white coating that is a defense from harsh summer sun. If you want to see its yellow blooms in spring, water infrequently and provide a hot sunny environment.
Christmas Cactus, Schlumbergera, is “toothless” as far as the cactus family goes, with its smooth segmented leaves and soft, rounded spines. Tubular flowers come in red, pink, orange, and white. This cactus species requires a departure from ordinary cactus care, as the plant hails from Brazilian rain forests where they live as epiphytes nestled in tree branches. Treat this cactus like any other houseplant, with moderate sun and frequent irrigation. As winter approaches and the plant is exposed to temperatures between 50-60 F you can coax this cactus to rebloom. Ask for my free Guide to Christmas Cactus Care when you visit the garden center.
Old Lady Cactus, Mammillaria hahniana, forms small colonies of ten-inch tall spheres, featuring white hairs and spines. Healthy plants often have a crown-like halo of pink blooms. Plant this cactus in a good quality cactus potting mix; water it every other week, monthly in winter. This cactus has a personality, just as its name suggests.
Rat Tail Cactus, Aporocactus flagelliformis, is a good choice in rooms with limited space. In a hanging basket, this fast-growing cactus can trail to three feet long. The plant is indigenous to Mexico, where the natives value its vibrant magenta blooms in traditional medicines for heart problems. As a houseplant, this cactus is fanciful, unusual, and very easy to grow.
FUN GARDENING CLASSES are coming up that are sure to green-up the thumbs of even novice gardeners. Classes are free, and are held at Watters Garden Center at 9:30 on Saturday morning:
October 26 – Fall ‘To-do’ List for a Healthy Yard – Get the most out of your landscape with this easy-to-use checklist of fall care. Whether you want to bring color to your fall gardens, reduce bugs next spring, or simply put your landscape to bed, we’ll tell you how with the tried-and-true, easy-to-do tips based on our years of experience.
Until next week, I’ll be helping local gardeners pick the perfect cactus here at Watters Garden Center.