Growing palms indoors
Potted palms can lend a touch of the tropics to almost any interior landscape. And a healthy, full specimen can be very beautiful, as long as it's well-maintained.
Not all palms are created equal. Some thrive only in a brightly lit sunny location, while others tolerate the lower light levels that are more typical of most Minnesota homes, especially in winter. Since a well-grown palm is not inexpensive, regardless of size, it pays to choose carefully, keeping light levels in its ultimate destination in mind as you shop.
If you're thinking of a dimly lit corner, forget it! Even the so-called "shade-tolerant" palms need fairly bright indirect light most of the day. Without adequate light your plant will lose all its lower fronds and look like a stick — or series of sticks — with a few leaves on top.
Here's a brief rundown on some of the palms you're most likely to discover at florists' shops and garden centers. You may find others, as well. Just make sure to learn their environ- mental requirements before you decide to invest in them.
Parlor palm or neanthe bella, Chamaedorea elegans: This slow-growing, dwarf palm has more shade tolerance than any other, so it's one of the best choices for relatively low light. A shrubby plant with many stems or "canes", you'll find it available in sizes ranging from only eight or ten inches -- perfect for a desk or coffee table -- to several feet. It maxes out around four to six feet.
Two close relatives, reed palm, Chamaedorea seifrizii, and bamboo palm, Chamaedorea erumpens, share the ability to survive in relatively low light, but may grow several feet taller, especially in a brighter location. All three of these palms — parlor, reed and bamboo — do best in reasonably warm temperatures. Keep them away from leaky windows and cold entryways where they'd be exposed to blasts of frigid air.
Kentia or sentry palm, Howea Forsterana, is a tall, stately, slender plant with gracefully arching large fronds. Kentia palms can withstand lower light levels better than most large plants, according to Richard Gaines, author of Interior Plantscaping. These palms do best in "medium" rather than "low" light, but are less sensitive to cool temperatures than the Chamaedorea species. Though slow-growing, a Kentia palm is capable of eventually reaching your ceiling, at which time you'd have to give it away...or move to a more spacious home. You can't prune palms back!
Lady palm, Rapis excelsa, lends a distinctively "oriental" look to interior landscapes. Like the Kentia palm, it's slow-growing and suitable for medium light locations. And like the Kentia, you'll find it priced on the high end of the scale, due, no doubt, to the long time it takes to grow to marketable size. Lady palms are shaped like shrubs rather than trees, with many thin stems growing from the soil. Their unusual dark green foliage consists of several leaflets on each frond, joined so as to remind you of fingers on a hand. (A lady's hand, no doubt.)
Areca palm, Chrysalidocarpus lutescens, is a tree or shrub-like plant with graceful, long feather-shaped fronds. Medium green foliage has a tendency to yellow when heavily fertilized; it's also fussier about over-watering, and more prone to root rot than some. Like parlor, reed and bamboo palm, Areca palm does best when growing conditions are relatively warm.
Don't be fooled by sooty-looking flecks on sheaths that form the stems of Areca palms; they occur naturally and do not signify insect or disease problems.
Chinese fan palm
Chinese fan palm, Livistona chinensis, and European fan palm, Chamaerops humilis, are prized for their unusual fan-shaped foliage. Fewer people are able to grow them indoors successfully though, because these two palms demand higher light levels. But if you do have a bright, sunny south or west-facing set of windows, either one of these palms could be an exotic addition to your decor.
Both fan palms are grown as single stem trees or multi-stem shrubs; you're more likely to find the shrub-form. Chinese fan palm has huge leaves that appear fringed at the tips, while European fan palm leaves are stiffer, more deeply cut and lacy looking.
Though their light requirements may differ, all these palms have similar needs when it comes to water and fertilizer. In fact, dried brown leaf tips or leaf margins, two of the most common problems facing indoor palms, are related — directly or indirectly -- to how they are watered and fertilized.
Keep palms relatively moist. In spring and summer, or when temperatures are warm and days are longer, water them as soon as their soil feels dry a little below the surface. Allow the soil to get slightly drier in winter.
It's important that potting soil drains well and containers you use have functioning drain holes. Water palms thoroughly, then spill or siphon off excess water that collects in the tray or saucer below the pot.
Fertilize lightly from late winter through early autumn, the time when houseplants are likely to grow most actively. A build-up of fertilizer salts in the soil results in those dreaded brown tips and edges, especially if you allow the soil to get too dry between waterings. If you're unsure about fertilizing, err on the side of too little rather than too much. You can always fertilize again, if necessary.
Finally, keep palm fronds clean. Spider mites are attracted to dusty foliage and can balloon into a serious problem, particularly in winter when relative humidity is low indoors.
Illustrations: Van Gieson, Susan and Kurtz, Regina. 1980. Interior Planting Design File. Van Nostrand Reinhold Company. pp. 22-24.