And the answer is: Bromeliads.
“Which houseplants can adapt to low light and don’t require frequent watering, but will flower anyway?”
It’s a question that tropical plant experts like Angel A. Lara hear regularly, particularly from those who have put other houseplants in jeopardy by subjecting them to this kind of no-frills regimen.
Unlike many houseplants, bromeliads tend to have “an easy disposition,” said Mr. Lara, the vice president for botanical horticulture at Marie Selby Botanical Gardens, in Sarasota, Fla. That’s because many of the ones marketed as houseplants are epiphytes.
Mr. Lara speaks from extensive hands-on experience. Epiphytes from four plant families — bromeliads, orchids, Gesneriads and ferns — are the central focus of study at Selby, a renowned research facility and popular visitor attraction that is celebrating its 50th anniversary this year.
Most epiphytes, or air plants, don’t sink their roots into soil to absorb moisture and nutrients, Mr. Lara explained. Instead, they use their roots to attach themselves to other plants, especially trees and shrubs, or sometimes rocks.
Epiphytic bromeliads derive sustenance not from the ground but from the atmosphere, and from other living organisms. Their specialized design — whether it’s a central, vase-like tank formed by a rosette of leaves; complex cellular structures on the foliage called trichomes; or both — allows them to gather and conserve water. They also use their tanks to collect organic matter like insects or bits of leaves.
All of this amounts to “survival tactics,” Mr. Lara said.
“They’re doing what desert plants do,” he added, likening it to the impressive water- and nutrient-storage capabilities of plants like cactuses. “But bromeliads are doing it in the tropics.”
With roughly 3,500 species — and probably 100,000 hybrids — bromeliads offer a staggering number of choices if you’re looking for a houseplant.
Mr. Lara recommends Tropiflora Nursery or Bird Rock Tropicals as mail-order sources. You may find yourself easily seduced by a hot-pink earth star (Cryptanthus) or the showy pattern of venation on the foliage of some big, standout Vriesea.
Most bromeliads have a couple of things in common: They’re stemless, usually with a rosette structure. And they’re native, almost exclusively, to the New World tropics and subtropics. (Only one species hails from West Africa.) But for the last 500 years, since the discovery of the pineapple — a terrestrial species, not an epiphytic one — bromeliads have been moved around the globe.
With the notable exception of Spanish moss (Tillandsia usneoides), a Zone 8-hardy epiphytic bromeliad (and an odd one out in appearance, too), these are generally Zone 10 plants. That makes them perennial garden candidates only in places like portions of Florida, California and Texas.
Everywhere else, they are happy outdoors only in the summer — and Mr. Lara recommends bringing them outside if possible, so they can stock up on resources before the leaner times of indoor houseplant season hit.
Starter Plants: Beginner Bromeliads
If you are new to bromeliads, maybe don’t start by going too big or too prickly at first, Mr. Lara suggested.
Such practical considerations figure into matching plant to place. For example, large bromeliads with rosettes of leaves deep enough to form water-holding tanks — like the spectacular Vriesea gigantea, or V. hieroglyphica with its banded leaf markings — may not be ideal for a busy family room, even if the other conditions are suitable.
“I have kids, and I have dogs,” he said, wincing at the vision of the ample tank’s contents upended onto the carpet.
Another consideration: Many bromeliads have spines on the edges of their leaves or are serrated, “and they do sort of scratch you up,” he said. “Bromeliads are notorious for being not the friendliest of sorts.”
Mr. Lara’s top-five list starts with gentler ones, like the pink quill bromeliad (Tillandsia cyanea, now classified as Wallisia but often sold by its former name). With green, grassy leaves that form a small tank, or water reservoir, it makes a good choice for growing bare root, in a slatted hanging basket, or mounted with zip ties onto a piece of wood. The fragrant flower scape — which resembles a big, flattened pink pine cone — lasts for as long as six months.
Next, he recommends the earth stars, or Cryptanthus. Among the most colorful and forgiving of all, they are easily grown in pots. Their wavy leaf margins are serrated, but not bitingly so. Unlike his other recommendations, earth stars are semi-terrestrial, often living on rocks and sand in the wild.
Another that he highly recommends is the torch bromeliad (Guzmania lingulata), a spineless species. (It’s at the opposite end of the spectrum from the genus Dyckia, which is gorgeous but fierce.) The red-flowered torch was the first ornamental bromeliad to catch plant collectors’ attention, back in 1776, but breeders have since introduced cultivars and hybrids with scapes of yellow, white, pink, purple and even green, all with small water tanks and suited to growing in pots.
His next suggestion: “Any other Tillandsia.” T. harrisii resembles a silvery pineapple top. Distinctive Tillandsia funckiana looks like what might happen if a giant caterpillar were crossed with a soft-needled conifer. Grow either one mounted or in a hanging basket.
Rounding out his list is the urn plant (Aechmea fasciata), which has been in cultivation almost two centuries, so it must be doing something right. Its big pink inflorescence can last half a year. Although the original species is spiny, that trait has been almost bred out of some of the hybrids, Mr. Lara said.
A couple of his intermediate-level choices: “The most tried and true” of the Vrieseas, he said, the flaming sword (Vriesea splendens, now Lutheria splendens), which is happy in low light. For brighter spots, try colorful Neoregelias, but be prepared to give them sufficient space to stretch out sideways over time. “Because they are stoloniferous,” he said, “they go all over the place.”
Including onto a Christmas tree. Bromeliads are such a signature at Selby that toward the end of this month, a tree of more than 20 feet high will be fashioned out of 750 or so Neoregelias secured to a metal armature. It has been a holiday tradition there since the 1990s.
Care and Feeding
Owing to their epiphytic nature, most bromeliads don’t need soil so much as a solid footing — something to grab onto, the way they would a tree in the forest canopy. Those that do get potted up, like the Cryptanthus, Guzmania or Aechmea, are best underpotted, or given pots that may appear to be too small. This can create the look of a mismatch, but it keeps roots healthier.
“The Bromeliaceae should have what we refer to as ‘a little pot and a big head,’ because if you’re doing the opposite, you’re going to rot that plant,” Mr. Lara said. Letting plants stand in a saucer of water will do the same.
He recommends using a potting mix labeled for Phalaenopsis orchids, which are also epiphytic. Such blends are typically heavy on the bark and may contain ingredients like sponge rock, coarse perlite and charcoal.
If you have bromeliads grown in pots, water them as you would any other potted plant. If a plant’s leaves form a tank — the way Aechmea, Vriesia, Guzmania and Neoregelia do — add water into it, too.
Cryptanthus, for example, don’t have such water-holding reservoirs.
“I don’t have to fill up this thing,” Mr. Lara said of the earth stars, because their leaves don’t form a tank. “I just have to water the pot, which we’re all used to doing.”
Misting is often recommended as the best way to water bromeliads grown bare root. But with Tillandsias in particular, Mr. Lara prefers dunking them in a bucket of water for a thorough soak. That may be necessary only every few weeks, or once a month in the low-light winter season.
Relying on misting alone, he said, you risk cultivating “zombie Tillandsias” — silvery ghosts that somehow continue to look good months after their demise. Oops.
Also important: Water Tillandsias in the morning rather than at night. “The plants are actively doing work at night, opening their stomas,” he said. “If you dunk them in a bucket of water, you’re pretty much waterboarding them, and they will drown.”
After dunking a plant, allow it to drain properly, upside down, on a napkin or towel before returning it to its upright growing position.
With the tank types, rinse the central reservoir in the sink or shower to flush out any water that would otherwise become stagnant and could rot the plant. “If you can dump out that water and add new, that’s ideal,” he said.
With either watering method, once a month, from spring to fall, add balanced liquid fertilizer to the water at half strength.
“In the forest, the plants rely on the bugs living in that massive cup and the leaf matter that’s falling, the natural components that are breaking down,” he said. “For us, it’s fertilizer.”
What probably startles beginning bromeliad growers most, even after providing diligent care, is the inevitable decline of the original or mother plant after it flowers. Don’t panic: This is part of the bromeliad life cycle.
Pups — new growth known as ramets — should be developing alongside the original plant.
“That dying plant is giving all its resources to the new ones,” Mr. Lara said.
Gnarly as it may look for a time, don’t rush to bid the old plant farewell. Wait until the ramet reaches a third of the mother’s size. Then it’s safe to remove the mother, or remove the offset and make a new home for it.
“Or even better,” he said, “give it to a friend.”
Margaret Roach is the creator of the website and podcast A Way to Garden, and a book of the same name.
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