Dormant period is best for major thinning or crown reductions. (December, January and February). For overall maintenance pruning that must be done during the growing season, never remove more than 25% of the foliage and always make proper cuts (no stub cuts, no flush cuts, minimal use of heading cuts, proper crown reduction cuts and no ripped bark). Use the proper tool for the size of cut you need to make. If you are not sure how to make good cuts, consult with someone who does. The first rule of pruning is that you do no harm to the tree. Making proper cuts and thinning such that the remaining foliage is uniformly distributed throughout the tree is more important than the date you choose to do the work. However, still try to do the major pruning in the dormant season for best results.
Once in the spring will do unless plant color and vigor indicate additional nutrients are needed. Use a balanced fertilizer, one that has a formulation containing all the major nutrients.
Date Palms and Fan Palms usually do not need regular fertilization. Queen Palms will need to be fed about every 45 days throughout the growing season. Palms require special micro-nutrient fertilizer formulations. Liquid formulations are available at nurseries. Palm fertilizer spikes are helpful if placed where they can be dissolved by irrigation. If you use a granular fertilizer, cultivate the area around the palm lightly to incorporate the fertilizer into the soil and then water it in deeply. Don’t apply the fertilizer up close to the trunk.
When to cut back shrubs
Rejuvenate your shrubs by hard pruning them in early spring after the last frost is over. This will control the height, encourage flowering and you will only need to do a little touch-up pruning during the summer.
Thinning Trees Prior to Monsoons
Most of our trees blow over because of poor root development as opposed to crown growth. Consult with a tree care professional or arborist about establishing good root systems. Yes, thinning will probably be necessary in most cases, especially if the foliage is dense and located higher up in the tree. Remember from the note above that the foliage should be distributed evenly throughout the tree. This means horizontally, vertically, inside and out. Trees that are raised too high without proper thinning are the first to blow over. If you make a practice of doing your major thinning in December, you will be that much farther ahead coming into monsoon season.
Plant Care Before a Freeze
Know the hardiness of your plants and be alert to frost warnings. Keep frost cloth available in preparation. Do not cover plants with plastic.