Can Mexican Palm Trees Be Topped?

Palm Tree Growth

• Palm trees are monocots and have only one seed leaf. The palm trunk consists of an inner cylinder and an outer shell of nonwoody material, both of which are alive. In contrast, broadleaved woody trees, which are dicots, have internal nonliving tissue and a thin layer of external live tissue surrounded by protective corky bark. Tree trunks and branches contain lateral buds that can grow if you remove the end of the branch or the top of the tree. Single-trunked palms such as Mexican fan palm don't have any lateral buds. A single bud about 18 to 24 inches down from the top of the tree does the growing for the palm during its entire life. Once removed, there is no chance for further growth.

About Mexican Fan Palm

• Native to northern Baja California, fan palms grow around desert oases where water is constantly available. They have shallow roots, and as a result, you can successfully transplant older palms. They have palmate leaves with leaf divisions making a fan shape. Thin-trunked trees can grow to 90 feet tall and can reach 150 to 200 years old. Although these palms have a limited natural distribution, they grow by the millions in warm-temperate landscaping around the world. They have moderate invasive properties in some areas.

Pruning Mexican Fan Palms

• The old, dead leaves of Mexican fan palm stay behind and layer themselves against the trunk in nature, giving the tree a petticoat that harbors wildlife. When you grow them a landscaping plant, you usually trim old leaves away. The University of Nevada Cooperative Extension Service recommends minimal pruning and gives guidelines for pruning practices. Never top a palm tree. Don't remove green, living fronds, only dead ones. Use clean, sterilized pruning equipment. Don't use climbing spikes, which permanently injure trunks. Prune off flowering stalks and seeds, but don't prune just for cosmetic effects.

Pruning Mistakes

• When you remove living fronds, it results in narrowed upper trunks called pencil necks. Removing living leaves robs the tree of nutrients and can result in decreased growth and mineral deficiencies. Inexperienced workers mistakenly treat palms like woody trees and cut off the top in an attempt to force branching or keep the tree short. Hire trained professional palm trimmers to prevent practices that kill or damage your palm tree. As the University of Nevada Cooperative Extension Service's Area Extension Specialist M.L. Robinson comments, "Few cultivated palms die of old age. It is more likely they will die of cultivation or landscape mistakes."