Perhaps the most important question to ask when discussing palm pruning is what a healthy, properly pruned palm should look like. It should have a green full-rounded head (not shaped like a feather duster or pencil point) with green fronds (as leaves of palms are called) right down to the bottom of the canopy. Correct pruning is a key component to maintaining palm health.
Why should a palm be pruned?
1) improve appearance,
2) reduce risk to people or property by falling fronds, particularly should the fronds fall from tall plants,
3) remove flower and fruit clusters, especially in public landscapes where falling flowers and fruit debris can be messy as well as hazardous
4) remove leaves or sprouts from the base of the trunk that may harbor vermin (unwanted critters such as rats, scorpions, snakes, etc.!).
What should be pruned from a palm?
1) removal of completely dead fronds and flower and fruit stalks is never a problem.
2) there is no biological reason to remove live green fronds, and no scientific research supports the notion that removing green fronds reduces future pruning requirements. Removal of green fronds puts undue stress on the plants.
3) the pineapple shape crafted at the base of Canary Island date palms is not necessary for the good health of the palm and may prove detrimental.
When should a palm be pruned?
1) dead fronds can be removed at any time for aesthetic reasons and to mitigate risk.
2) many scheduled commercial pruning practices center around the removal of not only dead fronds but flowering and fruiting stalks prior to the setting of the fruit.
3) palms flower and fruit once per year. In the Phoenix area, date palms (Phoenix sp.) flower in late spring (usually April and May) and fan palms (Washingtonia sp.) in late spring/early summer (May and June), so pruning activities should be scheduled towards the end of the reproductive cycle.
4) if pruning is completed prior to the end of the reproductive cycle, additional flower stalks may be produced. If you are not certain as to when to prune regarding the reproductive cycle, observation and record keeping will be the guide, regardless of species.