There are very few plants that can add a tropical ambiance and dramatic accents to our desert landscapes as effectively as palm trees. Although our selection of suitable palms is somewhat limited by cold winter temperatures and low humidity, there are still plenty of heat-loving and drought tolerant options to choose from.
The only palm tree found naturally in Arizona is the California fan palm (Washingtonia filifera), but there are many other landscape-worthy palms that are well adapted to our climate. They need plenty of sun and excellent drainage to grow. With those two requirements met, palms are extremely resistant to many of the pests and diseases that are common here.
Palms either have long, feather-type fronds, or wide fan-type fronds, and all of the plant’s vertical growth is from the very top of the stem where its fronds also originate. In general, the fan-type palms are slightly more drought tolerant than the feathery-leaved ones, but they all need regular watering to get established.
Spring and summer are great times to plant a palm because they grow fastest in warm weather. Even if planted this month, palms should have plenty of time to get established before cold winter temperatures set in. Almost all of the palms we grow will need protection from a hard freeze when they’re small, but their hardiness typically improves with age. A noteworthy exception is the cold-sensitive queen palm (Arecastrum romanzoffianum), which isn’t suitable for use in colder microclimates, but does just fine in frost free areas of Tucson.
If you’re unsure whether or not a particular palm will grow in your neighborhood, try looking around to see if any of your neighbors are growing it. If one of your neighbors has a nice big queen palm growing in their yard, then you probably don’t live in a colder microclimate, and you should be able to grow any of the palms that we sell.
If you live in a colder pocket of the city, but still want a palm for your oasis, try a Mediterranean fan palm (Chamaerops humilis). This slow-growing, mess-free palm is the hardiest species we grow, surviving temperatures as low as 5°F and topping out at only about 15-20 feet tall.
Some people are surprised to learn that palms are more like grasses than they are like trees. Their non-invasive roots are typically shallow, and unlike trees, they aren’t able to heal over damage inflicted on their trunks (which is why palms should never be climbed with spurs or nails). When watering, a deep soaking to the depth of 2 feet is recommended, and good drainage is imperative. Watering frequency will vary depending on your soil type and the weather conditions, but a 2-4” layer of mulch over the root zone will help extend the amount of time between water applications by regulating temperature and reducing water loss.
After a palm is established, regular fertilizing will help to keep it full and green. There are special “palm formula” fertilizers available on the market, but a good all-purpose fertilizer will do the trick, too. Spring and early summer are the prime times for feeding; fertilizing later in the year could spur frost tender growth when the plant should be slowing down in preparation for winter.
Palm trees need their green leaves to produce food and stay healthy, so it’s best to leave green leaves alone when pruning your palms. Brown leaves can be removed any time if you find them unsightly, but leaving them attached allows some palms to build up an attractive skirt that can help protect them from cold winter temperatures. Many palms will eventually shed dead leaves on their own, so tall palms growing over areas that experience more foot traffic should take higher precedence when it comes to keeping the canopy clean and trimmed. Unless the frond comes off without the use of a tool, it’s recommended to leave two inches of the stem (also called a petiole, or a boot) attached to the trunk.
Do you have a favorite palm for Arizona? To see a list of the types of palms we grow here at Civano Nursery, head over to our catalog, and click on the palm leaf at the bottom of the page to choose the palm category!