Spines and splendor in 'little gems'
Versatile, hardy cactuses ask only for drainage and sun
It started out as an innocent hobby. Ken and Deena Altman were fresh out of graduate school: Ken with a PhD in psychology and Deena with a degree in human development. The two had been growing cactuses in their backyard and found they had more plants than they had garden.Skip to next paragraph
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So they began selling their overstock to local nurseries. Then they entered the mail-order plant business. That was 25 years ago. In a true story of avocation becoming vocation, the couple now runs Altman Plants, a large plant supply and distribution business with several hundred acres of greenhouses and growing grounds in several states.
The Altmans supply roughly 50 percent of the retail cactus market in the US.
Though their plant repertoire now includes perennials, vegetables, herbs, and other plants, cactuses remain one of their main product lines.
"I love cacti," says Mrs. Altman. "Their structure, the geometry of the plants.... I really enjoy their bloom in the spring. To me, they are like living treasures. Each plant is a little living gem."
What makes a cactus a cactus? A botanist will tell you that cactuses are a special group of succulents native to the Americas. They have spines that emerge from special tiny round organs known as areoles. Cactus flowers are large and either white or fluorescent shades of yellow, orange, and pink.
Spines, of course, are a cactus's most distinctive, though most variable, feature. Spines can be small and silvery - or large and tough enough to be used as fishing hooks and sewing needles.
Interestingly, cactus spines are actually modified leaves. Why do these plants have spines? Experts think that spines protect them from hungry predators and shade them from intense sun. Spines also create buffer zones around the bases of the plants, reducing evaporation and directing precious dew toward the roots - an important function in hot, arid deserts.
Deserts, however, are not the only places where cactuses grow. There are cactus plants native to jungles and islands, and from sea level to the mountains. Their shapes and forms are as varied as the habitats they grow in.
In an effort to simplify things, growers categorize cactuses according to their shapes and growth habits:
Columnar cactuses have tall, cylindrical stems. Some, like the famous saguaro cactus (Carnegiea gigantea), grow more than 50 feet tall and form candelabra-like branches.
A barrel cactus is thick and spherical with heavy ribs. It grows from 1-1/2 to 6 feet tall. Golden barrel cactus (Echinocactus grusonii) is common in landscapes of the Southwest.
Pincushion cactuses are spherical or cylindrical. They tend to be less than a foot tall, solitary or clumping.
Opuntias come in two general forms: flattened pads that look like thick leaves but are actually flattened stems, and jointed, sausage-shaped stems.
Epiphytic cactuses grow on other plants rather than in the ground. Epiphyllum, known as orchid cactus, is one type.
With a bit of knowledge and a sense of adventure, you can grow cactuses almost anywhere, both indoors and out.
Don Martinson grows them near Milwaukee, but he does it in pots. In the fall, he moves them into his basement, where they overwinter on windowsills. The temperature of Mr. Martinson's basement ranges between 50 and 60 degrees F, about the same winter temperatures that his plants would experience in their native habitats.
Keeping cactuses dry enough is a special challenge for Martinson. "Here in Wisconsin, we can get rainy, damp weather virtually any time of the year," he explains.
"If some species don't get a chance to dry out, they easily turn to mush," he says.
Martinson plants his cactuses in a very free-draining potting mix to ensure that they dry out between waterings.
In an area of Tennessee where winter temperatures occasionally flirt with zero, Nancy Robinson has grown cactuses in the ground for 30 years. She grows mostly opuntia, the prickly pear cactus, which does well in the open, sunny areas of her garden.