Cooler days and clear skies draw people outside to work in their yards this time of year. Plenty of gardening chores make sense, such as cutting back frost-damaged perennials, freshening-up mulch and trimming bed edges. But there is a huge effort I see that makes no sense horticulturally: severe pruning of palms.
People are creatures of habit, so it’s not surprising to see repeated actions just because, “We always do it.”
I hope to save you time and money by explaining why you should not prune palms.
Although the cabbage palm is Florida’s state tree, it is not actually a tree. Palms are grasses. That “palm tree” in your yard is more closely related to a stalk of corn than an oak. That means the physiology is much different than your typical shade tree.
Palms have one growing point or bud, called the apical meristem. It is at the top of the trunk. All of the fronds generate from this bud. It takes four to six months before they unfurl from the top of the canopy.
As new fronds emerge, older fronds are pushed lower. You might think discoloration of lower fronds is a sign the older leaf is ready to drop. In reality, it is an indication the soil is deficient in nutrients the bud needs to create a new leaf.
Yellow speckles or brown edges on lower fronds is a sign the bud is pulling nutrients—usually potassium and magnesium—from older leaves so it can make healthy new ones. Cutting off those fronds while there is still green tissue makes a nutrient deficiency worse.
Plants are neat organisms that make their own food through photosynthesis. It can get really complicated, but the bare-bones idea is a green plant takes in water through the roots and carbon dioxide through leaf pores (stomata). Sunlight is trapped by chlorophyll (the green in those leaves) and a chemical reaction occurs, creating glucose (energy for the plant) and oxygen.
In addition to removing essential nutrients from palms when you remove green leaves, you reduce green leaf tissue surface area, which affects the palm’s photosynthetic abilities.
A common myth is making a “hurricane cut” will reduce breakage during storms. Research shows the opposite is true. Observations during the 2004 and 2005 hurricane seasons showed palms that were hurricane cut were more likely to have their crowns snapped than palms with full crowns.
Damaged or dead fronds should be removed before storms to prevent them from becoming airborne during a storm, but green leaves should remain on palms.
What about the fruit?
Yes, you can remove the fruit from palms without long-term effects. Just don’t fall into the trap of, “While I’m up here, I’ll just lop off a few fronds.”
For more information about gardening, tree care and related topics, visit sfyl.ifas.ufl.edu or contact your local UF/IFAS Extension office.