Respect palm fronds for a healthy, happy plant

If any type of plant can conjure thoughts of a desert oasis, it would have to be palms. Whether they are tall and willowy, or short, with multiple stocky trunks, they thrive in the desert as long as they receive a little attention.

The thousands of palms that you see in Southern Nevada landscapes are not producing crops like coconuts (our winters are too cold and our summers too dry) or dates, although there are many date palms around town. Some of these do produce fruit, but unless they are hand-pollinated, they will not be the plump delicious ones we would prefer.

Most of us have used the term “palm tree” at some point. Since they are tall sturdy plants that look much like trees, it is easy to see why palms would be mistaken for them. They are not woody plants, however; they are far from what we usually call trees. Surprisingly, they are more closely related to orchids or sweet corn than they are to oaks or ashes.

With so many palms in the region, you might think that every horticultural professional would know how to care for them. Sadly, this is not true. Uninformed landscapers and homeowners frequently maintain them in ways that cause them to become unsightly and unhealthy.

Planting palms is where the mistakes can start. Contrary to some “authorities,” these plants require more than pure sand as a growing medium. A well-drained sandy soil, amended with a little compost, will promote healthy growth.

It is so important to remember that palms are plants for oases; they must have sufficient water to thrive. A mature date palm will use as much water as a 700-square-foot patch of fescue turf grass, assuming both are irrigated correctly.

Unlike many other landscape plants, palms have a relatively small number of leaves, or fronds. One frond is one leaf, performing all the tasks of a leaf: photosynthesis, water transpiration, etc. A frond may have leaflets in either a fanlike or a featherlike arrangement, but it is one single leaf.

A mature oak tree can have 200,000 leaves. Our common Washingtonia species may have fewer than 30 on the entire plant. Date palms (Phoenix) can have more, as many as 180, which is still a puny number compared with the hardwoods. Palms are not deciduous and do not shed their leaves annually.

These fronds can live for many years. One may take five years to mature from the time it first begins to unfold as a juvenile. If one is removed while it is still green, the plant loses a significant portion of the tissue it relies on for growth. Cutting off these living fronds will generally not promote new growth; it will stunt it.

Nature has arranged the leaves so they protect one another when the wind is fierce.

Only dead fronds should be removed, unless one is broken or there is a disease affecting the plant. Even as they are dying, the nutrients in those fronds are being redistributed to the rest of the developing plant. If there are still essential elements in the frond, removing it can contribute to starving the plant.

“Topping” is a terrible practice where the top of a plant is chopped off with no regard for the rest of the plant. This is frequently done to a tree when it is interfering with utility lines. When shrubs are “hedged,” they are experiencing the same trauma. At least those plants can continue to grow despite the insult since they have multiple growing points.

If the top of a single-trunked palm is hacked off, that plant will not recover, since it has only one growing point, located about 2 feet (or less) from the top of the trunk.

Since green fronds should not be touched except in special circumstances, and the top of the palm should never be removed, what can one prune off with a clear conscience?

Dead fronds should come off, especially when they might be harboring insects and other pests such as scorpions or rats. Palm flowers are rarely attractive, so they can be removed, as can the fruits.

Some species produce fruits with many viable seeds that germinate where they are unwelcome. Unless you want to start a Washingtonia plantation (and you will), remove the fruits.

Although it is fun for me to come up with essays on desert horticulture, and I do hope people are enjoying them, it is important that this column meet the gardening information needs of readers.

Do you have a pressing horticultural question? I will do my best to answer it with a research-based, unbiased reply, or even an essay.

Angela O’Callaghan is the Social Horticulture Specialist for University of Nevada Cooperative Extension. Contact ocallaghana@unce.unr.edu or 702-257-5581.