We have many different species of palm trees on Marco Island due to our favorable climate for their growth. They come in many shapes and sizes from large majestic trees to small shrubs. Some have single trunks while others have multiple trunks. All but our native palms come from a more tropical climate than ours. Occasionally our winters can be very cold by sub-tropical standards and our more tropical plants and palms can suffer some stress and cold damage. As summer arrives these damaged palms begin to decline leaving people wondering what is wrong with their palm trees. The basic premise is that it is not really possible to determine whether your ailing palm is due to disease, nutritional deficiency or cold damage until at least July of the following year. A simple time line for damage after cold is as follows. Leaf damage within a few days, spear rot (the area of new growth) after several weeks, bud survival will not be known for six to eight months but watch for new growth in July and micro-nutrient deficient leaves for several months due to cold non-functioning roots. What to do? Do not remove leaves until the cold is gone. If there is any green on the leaves, the tree will use nutrients from that leaf for recovery. Remove the spear leaf if it is rotten and easily pulls out and then drench the heart with copper fungicide. This is a good anti-microbial activity not an attempt to control disease. Even though the central spear rotted the meristem (growth point) may still be alive and re-sprout as noted above.
A very important task is to fertilize to give the palm the nutrients it will need for recovery. Not just any fertilizer will do. They are recommending a special blend of 8-2-12. Not all 8-2-12 blends are created equal however. You should read the label and look for slow release Nitrogen, Potassium and Manganese (large white, prilled Kieserite). The Boron should also be granular slow release. The magnesium and iron should be water-soluble. Shop around to find a dealer that carries this blend or something similar.
When applying fertilizer to your palms, the best method is to scatter the fertilizer on the ground below out to the drip line of the fronds. Deep root injections simply shoot the fertilizer below the majority of roots and into the ground and water below. Don’t waste your money or time with this practice. If you have trees surrounded by pavement or other hard scape features attempt to scatter fertilizer on any exposed soil surface out to the drip line and beyond. Foliar applications are another method.
We use palms in the landscape as specimens, border plants, hedges and even as patio trees in pots. Specimen plants used individually have a distinctive quality that adds an immediate tropical look. For border or hedge plants palms with dense foliage help screen or fill in an area. Smaller species with little or no shedding problems are excellent for patios. Be sure you choose the right palm for the right place.
Some palms are self cleaning, meaning they shed their fronds, while others will need to be cleaned occasionally to rid them of brown fronds and falling fruit.
Some of the more popular self cleaning palms are the areca palm, Christmas palm, royal palm and the foxtail palms. These palms will save you in maintenance costs but there will be debris to dispose of on a regular basis. The royal palm fronds can be very heavy so this tree should be placed in the landscape very carefully. Royal palms should not be planted where they may be dangerous to pedestrians and automobiles beneath them. A stand of areca palms, while providing a wonderful, tropical screen for privacy can produce a truckload of fronds for disposal each week.
Some of the more popular palms which will need cleaning occasionally are the queen palm, washington palm or coconut palm. When cleaning palms which don’t readily shed their fronds you should do so very carefully. Pruning can remove food reserves stored in the fronds and also leaf surface area which decreases the tree’s ability to harvest sunlight for more food. Palms also take moisture from the air through their fronds. If the frond is green leave it on the tree.
A practice called “hurricane cutting” is not a good idea. This practice involves removing not only the dead, brown fronds but also beneficial green fronds leaving only a few fronds sticking straight into the air like a telephone pole. Not a pretty sight. Also very bad for the health of the trees for all the reasons listed above plus severe cutting of the fronds stunts root growth which will in turn stunt the tree’s growth and leave it susceptible to other diseases. This practice will also lessen the diameter of the trunk and weaken the area near the heart or bud of the tree making it more likely to be damaged in high winds.
I read an article suggesting you should never prune a palm tree, period. While this is a good idea in theory, dirty palms are not aesthetically pleasing to most people. I personally don’t prune my palm trees. I find the skirt of brown fronds hanging to be attractive. Old fronds which stay on these palms attract nesting insects and rodents. The insects are good food for birds and I’d rather have the rats in my trees than my attic. Mature coconuts can be dangerous much the way a royal palm can be. A mature coconut palm can be 100′ tall. A coconut falling from that height onto your head would really hurt! You can prevent the formation of palm fruits by removing the flower stalks as they emerge.
When pruning palms be careful not to cut or injure the terminal bud or the whole tree could die. Cut the fronds from the underside to avoid tearing the fibers of the palm’s stem.
The most important thing to remember is if the frond is green, the tree is still using it so leave it!
An exception to this rule is the transplanted sabal or cabbage palm. The survival rate for these palms transplanted without fronds is 95% compared to 65% of those transplanted with one third of their fronds remaining. In addition to lower survival rates for palms transplanted with fronds the fact that all original fronds will die and will have to be removed later makes this practice costly in terms of labor. Complete frond removal appears to be the best method for transplanting sabal palms which lose all their roots in the transplant operation.
Trimming palm trees is a dangerous and precise procedure which should be left to professional tree trimming companies with an understanding of proper pruning practices. Just remember to go easy on them if you want healthy and attractive palm trees.