How to Grow and Care for Palm Trees Indoors
There are about 2,600 species of palm trees spread over 181 genera within the Arecaceae family of plants. Most are tropical or subtropical in origin, native to spots like South America, Asia, and the Caribbean. Most palms can be distinguished by their large, compound, evergreen leaves (known as fronds) that are arranged at the top of an unbranched stem.
In addition to their role as landscape trees in warmer climates, palm trees can be distinctive and wonderful indoor plants. Mature palms often adorn public spaces and foyers, adding an elegant and distinctly tropical air to the decor. At the same time, very small, immature palms can be used as a pop of greenery in homes.
It is tempting to think of palm trees as purely tropical plants—give them plenty of sunlight and water and they will be just fine. However, there are also desert varieties that will drown from too much water and still other varieties that cannot thrive without fertilizer. Careful research on the particular species of palm you end up choosing is essential to growing it successfully. As a general rule of thumb, most palms can be planted in the early spring and will grow slowly, often adding less than 10 inches of height a year.
Palm Tree Care
Palms are a group of plants that includes thousands of species from various biomes all over the world, and each has its own diverse needs. There are tropical, subtropical, and desert species, as well as palms that grow in cold-weather climates like Alaska. Some are understory plants that prefer shade and a moist, dark environment, while others love heat and sunshine. A good rule of thumb, if you want healthy palms, is to make sure you feed them frequently—whether you're growing them indoors or outdoors.
How to best display your palm depends on its specific size and growth habit. Many are perfect indoors as corner-specimen plants or foyer plants. Likewise, palms do very well in groups with smaller potted plants clustered at their base. Wherever you locate your palm, try to avoid placing it somewhere that experiences a lot of traffic brushing against or pulling on the fronds, as this will weaken (and possibly kill) the plant.
Keep in mind, your palm will likely not flower indoors, either. Many of the common species won't live long enough to flower or reach a mature size when kept as houseplants. Remember, some of these are full-fledged trees in the wild, so the lack of flowers is more than offset by the majestic spread of the plant.
If you take good care of your palm, there is a possibility that fronds could be brushing against your ceiling after a few years. Unfortunately, you can never top-trim a palm tree, as all palms grow from a central tip. If you remove the growing tip, the plant will die. So if you have a nearly-mature palm bursting from your house, congratulations—the next step is to seek a nearby hotel or office building looking for a wonderful interior plant.
One of the reasons palm plants are such common houseplants is that they can easily adapt to low-light conditions. Most palms are tolerant of (or prefer) shade and may fail to thrive if they receive too much direct sunlight. Low-light palm species prefer bright indirect light but also can tolerate less light, especially during the winter months.
The best soil for palm plants is a loose, porous mixture, like a combination of peat moss, leaf mold, and shredded bark. You can buy a cactus or palm soil mixture specifically made for growing palm plants—otherwise, they will grow just fine in a general-purpose commercial potting soil. If you're someone who tends to forget to water your plants, mix some peat moss or vermiculite into the general-purpose potting soil to help retain moisture.
Good drainage is essential for healthy palm plants. Just because palms live in warm (sometimes tropical) regions does not mean they enjoy being waterlogged. In fact, many palms grow best in slightly sandy soils with ample drainage. Never let a palm's root ball sit in water and allow the plant's soil to dry out in-between waterings. You can also choose to plant your palm in a vessel made from terracotta or clay to help wick excess moisture from the soil.
Temperature and Humidity
Few palms will thrive in truly cold temperatures, and some, like the coconut palm, cannot tolerate any cold at all. Cold-hardy palms include the parlor palm and kentia palm, which explains why these are among the most popular indoor palms. As a general rule of thumb, palms prefer temperatures no lower than 50 degrees Fahrenheit.
Feed your palm regularly during its growing season. If possible, choose a palm fertilizer, which contains all the required micronutrients for a healthy palm, as well as extra potassium and manganese. Potassium deficiency is especially common in palms and can result in yellowing or brownish fronds. If you notice your palm turning, it may be time to increase your feedings.
The temptation to trim fronds is hard to resist, but many species of palms draw nutrients from old fronds long after they have begun to yellow or brown. It's a very common mistake to over-prune palm trees, which can weaken the overall plant and rob it of valuable nutrients.3 In general, remove only fully browned leaves and never cut your palm down to just one or two new fronds.
Common Pests and Diseases
Indoor palms trees are often prone to potassium deficiency, signaled when the oldest leaves begin to die back, beginning with the tips. A controlled-release potassium supplement is the best treatment. But if the tips of all leaves turn brown, it is often due to excessive fertilizing.
Like other houseplants, spider mites, mealybugs, and scale insects can be a problem, especially if your palm trees are kept close to other houseplants that may be infected. Keep an eye out for telltale signs of infestation and treat the plant promptly using insecticidal soap or horticultural oil such as neem oil.