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Month: November 2015

Cacti and Succulent House Plants

Kalanchoe blossfeldiana
The colorful Kalanchoe blossfeldiana blooms for a long period in winter. (photo by Jessie Keith)

If the ideal house plant existed, it would be a specimen that combined eye-catching good looks with the ability to survive on a diet of almost total neglect. That kind of perfection is unattainable, but succulent house plants come close.

Native to dry climates and situations, succulents have evolved over the millennia into efficient water-storage vessels, hoarding precious moisture in fleshy leaves and stems. The sheer number of available species and varieties is enormous and includes sedum, aloe, euphorbia, sempervivum, jade plant, hens and chicks, kalanchoe, many types of desert and jungle cacti, aeonium and living stones. Shapes, sizes, and colors vary widely, from the complex rosettes of “saucer” aeonium (Aeonium tabuliforme) to the statuesque beauty of a mature jade plant (Crassula ovata). Succulents practically beg to be shown off and grow equally well in standard containers, grouped in dish gardens or mounted as living wreaths.
Some of the most interesting and colorful types are described below.

Suite of rosette echeveria succulents
A suite of rosette-forming succulents for indoor growing. (photo by Maureen Gilmer)

Thorns and Rosettes

A relative of the common holiday poinsettia plant, crown-of-thorns (Euphorbia milii) is among the most popular of the many euphorbias. Evergreen, shrubby and succulent, it reaches about two feet tall as a houseplant. Crown of thorns is also true to its name, featuring intimidating thorn-covered stems. Rounded flower clusters with large, petal-like bracts in shades of red, yellow, orange, white or peach help compensate for the prickles.
If you prefer rosettes to thorns, try tree houseleek (Aeonium) or hens and chicks (Echeveria), both of which bear flower-like rosettes of fleshy leaves in colors ranging from silvery gray-green to reddish bronze. Some species, such as Mexican snowball (Echeveria elegans) are also noted for their showy, bi-colored flowers

A Cast of Many Cacti

Not all succulents are cacti, but all cacti are succulents. True cacti are members of the Cactaceae family and many of the best known are covered with the protective prickles for which the clan is famed. Handle household cacti with care and keep them away from children and pets. Prickles aside, cactus family members boast interesting shapes, colorful flowers, and undemanding natures, making them excellent houseplants. Traditional favorites include the shaggy “old man” cactus (Cephalocereus senilis), an erect, columnar plant covered with long white hairs. It has the potential to grow tall but does so very slowly.

Succulents in pots
Succulent collections such as these need to be separated and repotted after a year or so, if each plant to grow successfully.

Little Bolivian cactus (Rebutia puchella) is part of the genus sometimes known collectively as “crown cacti”. Growing only about six inches tall, it bears batches of vivid orange blooms in summer and succeeded handsomely in a small container. Another low grower with bright carmine-pink flowers is rose pincushion cactus (Mammillaria zeilmanniana), which features a rounded form and summer blooming habit. Like Bolivian cactus, it is small. A four-year-old specimen is likely to be only four inches across.
Many mammillarias, with their appealing rounded shapes, succeed as houseplants. In addition to the rose pincushion type, popular species include snowball or powder puff pincushion cactus (Mammillaria bocasana) and silver cluster cactus (Mammillaria prolifera), featuring a plethora of small, silvery globes sporting bright red blooms.

Holiday Cacti

Though they are part of the cactus family, holiday cacti (Schlumbergera spp.) are rain forest natives. Christmas, Thanksgiving and Easter cacti are closely related species, distinguished from each other by bloom time and leaf shape. Many commercially available varieties are hybrids. All holiday cacti all feature sprawling, succulent “leaves” that are actually flattened stems. The bright flowers produced at the stem tips run the gamut of the color spectrum, with the exception of green and blue. In the fall and winter, holiday cacti are sold in bud, ready to bloom for the celebration season. They can easily be kept and nurtured for years afterward.
Holiday cacti need somewhat less light and more frequent watering than their prickly cactus cousins. Position away from direct sunlight and promote flowering by placing pots on trays filled with pebbles and water.

Holiday Cactus
Holiday cacti (Schlumbergera spp.) are some of the must colorful succulents for the holidays.

Kalanchoe

Another succulent that lends color to the winter houseplant array is kalanchoe (Kalanchoe blossfeldiana). The upright plants are distinguished by fleshy, scalloped leaves that set off the clusters of small, bright flowers held above them. The flower color range is roughly the same as for holiday cacti and double-flowered kalanchoe varieties are widely available. Related to the jade plant, kalanchoe is a medium-sized specimen, growing up to eighteen inches tall. Under normal home conditions, the blooms last up to six weeks.

Succulent Care

Good succulent care begins with high-quality, free-draining potting medium, like Fafard® Cactus & Succulent Potting Mix. With the exception of holiday cacti, most succulents thrive on at least four hours of sunlight per day and relish the low humidity of the average home in winter. Indoors, position the plants in your sunniest window. The quickest way to kill succulents is by overwatering, so let the potting mix dry out thoroughly between waterings. Feed only during the active growth period—spring and summer—and use either a specialty fertilizer according to package directions or general-purpose fertilizer diluted to one-quarter strength.

All About Amaryllis

The bright, bold blooms of Amaryllis add to the holiday festivities. (photo by Maureen Gilmer)
The bright, bold blooms of Amaryllis add to the holiday festivities. (photo by Maureen Gilmer)

Amaryllis are emblems of the winter holiday season, their bold, flamboyant flowers decorating everything from greeting cards to wrapping paper to the holiday table itself. Known botanically as Hippeastrum, they trace their origin to a number of Hippeastrum species that inhabit the anything-but-wintry forests and slopes of tropical South America. Plant hybridizers have interbred these species over the past 250 years, ultimately producing the showy-flowered, large-bulbed amaryllis hybrids that populate garden centers and bulb catalogs in fall.

Amaryllis gifts
Amaryllis, and other bulbs for forcing, can be found pre-forced or boxed for winter forcing.

Obtaining Amaryllis

Purchased amaryllis bulbs put on a lavish display with ridiculous ease. Most come from overseas growers, who have conditioned the bulbs to provide immediate gratification upon planting. Take an amaryllis bulb, half-bury it in a free-draining potting mix (such as Fafard® Natural & Organic Potting Soil with Resilience™), add water, and – voila – it happens. Plump, spear-shaped buds arise on thick fleshy stems, achieving spectacular full bloom within a few weeks after planting.

Many amaryllis are sold pre-installed in a plastic pot. More satisfactory, however, is a deep clay pot, which provides ballast to counterbalance the weight of the huge blooms. Plant the bulb with its top half exposed, to give the roots maximum growing space. Bright light and relatively cool temperatures (60 to 65 degrees F) result in stockier growth, which also discourages toppling. An east-facing windowsill is ideal.

Bringing Amaryllis to Bloom

Bringing purchased amaryllis to bloom is a cinch. Coaxing it to repeat the performance is a trickier proposition. To rebloom, the bulb needs a period of dry rest, approximating what its ancestors experience in the wild. In their native habitats in eastern Brazil and in the foothills of the Andes, most Hippeastrum species produce flowers and foliage during the spring and summer rainy season, becoming quiescent when the weather turns drier in fall and winter.

Amaryllis hybrids in cultivation require a similar wet/dry treatment. Regular watering and feeding after bloom, followed by withdrawal of water in summer, will typically trigger a new round of flowering when watering is gradually resumed in late fall. Many amaryllis fanciers move their plants to a partly shaded outdoor location after the last frost date, bringing them back inside for their dry rest period. Plants generally do best if left in their containers and repotted only when absolutely necessary (once every 4 or 5 years should do).

Amaryllis 'Dancing Queen'
Amaryllis ‘Dancing Queen’ is a pretty double form. (photo by Pam Beck)

Dutch Amaryllis

Hybrid amaryllis bloom in a variety of colors, sizes, and shapes. Best known are the large-flowered Dutch hybrids, with immense, wide-flaring, six-petaled blooms that owe much of their form and coloration to the red-flowered Bolivian native Hippeastrum leopoldii. Old-time favorites from this group include ‘Red Lion’ (introduced in 1958), pink-striped ‘Apple Blossom’ (1954), and white, crimson-edged ‘Picotee’ (1958). More recent introductions – such as velvety burgundy-maroon ‘Red Pearl’ and tangerine ‘Naranja’ – are gradually supplanting some of the old standbys. Also relatively new to the scene are a race of Dutch Hybrids that bloom in 4 to 6 weeks from planting, rather than the typical 8 to 10. These “Christmas-Flowering” amaryllis come in the customary range of whites, pinks, and reds.

Double Dutch Amaryllis

Other hybrid groups include double-flowered Dutch Hybrids (such as purple-red-striped ‘Double Record’ and pure white ‘Ice Queen’) and miniature amaryllis. The latter have the appearance of scaled-down Dutch Hybrids, bearing 3- to 4-inch (rather than 8- to 10-inch) blooms on somewhat shorter stems (10 to 16 rather than 18 to 24 inches).

Butterfly Amaryllis

Hippeastrum aficionados have many more groups of hybrids to explore, as well as the species themselves. Selections and hybrids of the butterfly amaryllis, Hippeastrum papilio, offer several takes on its curious green and maroon, asymmetrical flowers (look for ‘Grafitti’ and ‘Papilio Improved’). Hippeastrum cybister has lent its narrow-petaled, spidery form to a growing number of hybrids including ‘Chico, ‘La Paz’, and ‘Emerald’. And trumpet-flowered amaryllis such as raspberry-striped ‘Santiago’ and candy-pink ‘Estella’ – with elongated, funnel-shaped blooms – are becoming increasingly available from bulb sellers.

Amaryllis in different stages
Amaryllis bulbs at different stages of forcing. (photo by Maureen Gilmer)

Gardeners in USDA zones 7 and warmer can even try amaryllis in the garden. Hardiest of all is St. Joseph’s lily, Hippeastrum x johnsonii, whose trumpet-shaped, crimson, white-starred flowers (on 2-foot stems) have ornamented Southeast U.S. gardens since the mid-nineteenth century. So, too, have the dazzling crimson blooms of oxblood lily, Rhodophiala bifida, which look for all the world like dwarf amaryllis (indeed, the species was formerly included among the Hippeastrum). Both make wonderful subjects for gardens from the Mid-Atlantic southward, the trumpets of oxblood lily providing a late-summer echo of St. Joseph’s lily’s spring display. Dutch Hybrids (and many other Hippeastrum hybrids and species) are candidates for gardens in the lower South, where they’ll winter over with minimal protection.

Whatever their season or place of bloom, few bulbs bring greater cheer than the members of the Hippeastrum tribe.