Fertilizing in Florida is always a challenge. What, when, where, how, but mostly why are questions I get from clients regularly. The feeding and maintenance of both new and old plants usually involves the application of balanced fertilizer three times a year, every year— March or April, June or July, and September or October. Fertilizer just went back on sale in the box stores October 1. If you don’t have your lawn and yard professionally sprayed, you will need to fertilize your plants yourself. Time-release pellets are easier and safer for the plant as they break down slower and more gently. Check to see the application frequency needed per product on the label. Apply time release pellets fertilizer (Ozmocote or Dynamite) like salt and pepper. Do not just pile a mound at the base of the plant, in the case of fertilizer, more is not better! Sprinkle only enough to clearly see it on the soil. Apply a width depending on size of plant, e.g. a larger tree you might apply a 2-3 feet wide, small shrub, a few inches. I like the fat tree spikes and use them for both trees and shrubs that come in a small bag of 5 and can be bought at the box stores.
I use the Ozmocote and Alaska Fish Emulsion in my own yard and garden. Alaska Fish Emulsion is an organic fertilizer (ground up fish parts) and works wonders on all plants. You can use “fish” anywhere and everywhere since it now comes in a non-smelly formula. You can not burn or overdose using fish. This can also be used as a “tonic” for sick plants, 2x or 3x strength over 2-3 waterings. You can also use fish for planting by watering it into your soil instead of plain water to promote quicker adaptation.
Our sandy Alkaline soil can affect many plants that require acidic soil conditions. Some familiar acid-loving plants include Ixora, Magnolia, Azalea, Gardenia, Hibiscus, and Roses. Use acid fertilizer made specifically for these plants. Planting these plants near oak trees, which makes the soil more acid, helps this situation.
What is really in the fertilizer bags? What does it all mean?
Here is a break down for their use;
The top of a fertilizer tag lists three numbers for the major plant nutrients:
Nitrogen (N) Phosphorus (P) Potassium (K)
These are also known as the N-P-K number. The most common is 6-6-6, or Triple 6.
Nitrogen The first number is the element that makes top green vegetative growth. It is also the least expensive way to make your grass and plants green. There is a downside to this. Using a fertilizer that is much above 10% also makes soft growth: the leaf that bugs just love, much easier for them to get their proboscis or teeth into. Look at grass fertilizer tags (they are usually the highest in nitrogen). The first number is usually quite high (16 to 36%). Not only do you have to cut the grass more often, but also you end up with more disease problems. In addition, water release fertilizers are the easiest to burn with, which is why inexpensive fertilizers have very low application rates.
PHOSPHORUS (P) The second number is for the element that affects roots, stems, fruits and flowers. Grass fertilizers use too much nitrogen (to “keep it green”) and completely ignore root system health (roots are the part of the plant that take in and process the food). The middle number in grass fertilizers is usually between 4 and at the most 6.
POTASSIUM (K) The third number is for the element that promotes flowers and fruits. It also enables assimilation of Nitrogen and Phosphorous. It is used by the plant to make strong cell walls, which makes it more difficult for bugs and disease to get into the plant.
MINOR (ESSENTIAL) ELEMENTS This section lists other elements that plants need in much smaller quantities. Manganese, magnesium, iron, etc., make your plants green with safe growth. Florida’s sandy soil does not have many minors, so they must be added. Without them, the majors are not assimilated properly through the plant’s system. Underneath each element is listed where it was derived from. Do not think that a bag that says 20-20-20 is automatically 10 times better than a bag labeled 2-2-2. No plant wants or needs 20-20-20. You will want to get the right fertilizers for your plants.
1. USF recommendation for palms is to use 8-4-12. Palm fertilizer should automatically include 3-4% of both magnesium and manganese. Read the back label to be 100% sure these are in your palm fertilizer. Sensitive palms like Pygmy date palm, Foxtail, Queens, Royal palm, and Paurotis will probably die without these critical nutrients, magnesium and manganese.
To add magnesium you will save money if you purchase Epsom Salts at your drug store. Epsom Salts is magnesium sulfate. Always apply at the same time with an application of your regular fertilizer for that plant (to prevent imbalance)