Houseplants have been indoor guests for thousands of years; hieroglyphics show their popularity in ancient Egypt, while history records the use of atrium rooms, similar to our sunrooms of today, by the ancient Greeks and Romans. Fast forward to the 1400s, when explorers sailed the oceans blue and returned with new species of tropical plants. The whole idea of growing plants indoors 'took root.' The challenge, however, was that darn ocean voyage. The survival rate of these tropical plants being tossed around and subject to dark, dank, below-deck quarters and constantly changing environmental conditions was poor, to say the least. By the mid-1800s, an enclosed glass box that allowed the plants to be safely transported was conceived and became the precursor to today's terrarium. A new challenge arose: With all of these exotic plants being raised indoors with minimal light, heat and humidity, a better way to tend them was needed. The predecessors to today's greenhouses and conservatories, 'orangeries,' were invented. It wasn't until the late 1950s that houseplants caught on in the states, mainly because many folks did not have consistent heat during the winter months. If the stove went cold, the plants froze. It's estimated that the houseplant craze took serious hold here in the early '70s, really not all that long ago, if you think about it. Take a trip to the southern coast of the United States or a visit to a Caribbean island, and you're sure to see a houseplant you're familiar with growing alongside the road or in a manicured landscape. Take notice of where they are growing, because the trick to growing them indoors is to mirror those environmental conditions. Some love humidity, others full sun, and still others the tranquility of a shady location under the canopy of a big tree. Shade-loving, tropical plants do best in most homes and offices. Shopping malls are great places to get ideas for low-light plants. There, all they receive is either artificial lighting or muted natural light from skylights high above. In our homes and offices, low light is typically considered a north- or east-facing window, or a location across the room from a south- or west-facing window. Ah, but who are these tropical shade-worshippers? The vast families of Philodendron and Epipremnum aureum, also known as Pothos or Devil's Ivy, top the list. Philodendrons can be grown as hanging baskets, floor or desk plants, or trained to climb slabs of bark or other decorative trellises, depending on the variety chosen. Pothos and Devil's Ivy are typically hanging plants. All are not only outstanding for low-light conditions, but also low-maintenance, hence their popularity in indoor planters at shopping malls. Though not as tolerant of low light, other options are Aspidistra elatior, or cast iron plant; Aglaonema commutatum, or Chinese evergreen; the family of Dracaenas; Caryota mitis, or fishtail palm; Raphis excelsa, or lady palm; Sansevieria trifasciata, or the snake plant, aka mother-in-law's tongue; Spathiphyllum wallisii, or peace lily; and many members of the Peperomia family. I highly recommend you cruise the aisles of your neighborhood greenhouse and see what plants are available. Don't be quick to choose just any plant. The family of Philodendrons, for example, can offer some pretty spectacularly textured and shaped leaves, from heart-shaped to deeply cut to some that look to be so thick you'd think they were artificial. If a deeply wrinkled and crinkled leaf appeals to you, the family of Peperomia is for you. Its deeply fissured, heart-shaped leaves grow at the tip of each straw-like stem that protrudes from the crown; just a cool-looking plant. Unfortunately, most low-light plants won't offer a flower, so you'll need to rely on leaf color to add pizzazz to the room. Pothos come in variegations of green and white, green and yellow, and a pure, almost chartreuse yellow; it's stunning, I might add. The cast iron plant has a green leaf mottled with silver streaks, and the infamous snake plant can be found in variations of solid green, green and yellow, or green and white. You can always pot a few different plants together, as long as they observe the same moisture and light conditions. I have a dark green snake plant potted with a yellow-and-green pothos. I've hung the pot in a jute hanger; the pothos cascades, while the sword-like leaves of the snake plant point upward. Like any plant, if it's not happy, it'll let you know. Some tell-tale signs include fading leaf color, leaf drop, bending or stretching toward a light source, smaller new leaves, or no new growth during the growing season. Should any of these occur, just move your plant and watch. Houseplant season is a great way to continue our love of gardening indoors. Walk a mall and check out the plants, then visit a greenhouse and bring one home for that cozy corner that needs a little greening. (Nancy O'Donnell owns Perennial Graphics Nursery in Schaghticoke, N.Y. Contact her by e-mail at dodonnell@nycap.rr.com. Gardener's Notebook can be found at http://timesunion.com/life.) 