Just what is a "high middle number fertilizer" all about? Coming from a horticulture background this high middle number for blooming was puzzling to say the least. My schooling, attending horticulture seminars specifically about fertilizers and the many years involved in most aspects of the "Green Industry" I had never heard of this "high middle number for blooms phenomena". Also, this was not how we had been successfully raising and fertilizing plumeria (at that time) for the past 30 years. We even did tests to see these "spectacular results". This was unimpressive to say the least. In the past a high middle number fertilizer was a specific fertilizer for the feeding of transplants. Why? According to horticulture science phosphate's first and foremost purpose is promotion and development of the root system.
Why have the Big Corporate fertilizer Manufactures changed scientific facts?
The simple answer is "big corporation marketing ploy" strictly for big corporate profits. They want you to think "high middle number" and that you cannot get an abundance of flowers without their latest fertilizer. This is far from the truth. In addition, these fertilizers are produced with the cheapest synthetic ingredients possible. Phosphate is very important for "blossom set" however no effect on quality or size of flowers. "High middle number" fertilizers are meant for short term use. An overabundance of phosphate will lower the ph of the soil to the detriment of the plants uptake of nutrients. Another reason is they are out of balance and do not supply adequate potassium for a healthy plumeria growing out of its natural habitat. In Southern California there is no tropical habitat for growing plumeria. In addition, the materials used in these products have shown to contain an over abundance of chloride (C1).
There have been specific fertilizer formulations for years targeting citrus and avocados, fruit trees, tomatoes and vegetables that have been helpful for the home gardener. These were made not only for blossoms i.e. fruit production but for the over all health of the specific plant. There was never in the past "high middle number" fertilizer in these type of products. "High middle number" fertilizers are infiltrating this market to the detriment of the home gardener. "High middle number" fertilizer will never supply the appropriate combination of nutrients to bring your plumeria or any plant for that matter to overall optimum growing condition.
The reader should ask the question how much phosphate (P) "high middle number" does a plumeria need to bloom? Does any horticulture science agree with both the plumeria sites and manufactures promoting "high middle number"? You will find a positive "NO". Results from our latest research proves without a doubt NO. And a web search will give you the same answer.
Just because someone calls themselves a "plumeria expert" that does not necessarily mean they are. On the Plumeria Societies and a very popular plumeria site there are pages where writers extol the use of "Super Bloom" which is "12-55-6" and "Super Blossom Booster 10-50-10".
Just what "nutrition" is the plumeria grower getting from using a "high middle number" plumeria fertilizer? We will use the following as an example for the math:
"Green Light Super Boom" directions tell the grower to use one teaspoon (t) per gallon each feeding. I will use the common acronym "PPM" which is defined as Parts Per Million.
1 teaspoon (t) equals;
158 PPM of Nitrogen (N) 319 PPM of Phosphate (P) and 66 PPM of Potassium (K)
There are two problems with these numbers first the phosphate;
At two hundred parts per million science has proved beneficial soil bacteria's including the "good fungus mychorrizae"
Phosphorus will move only 1/10th of an inch in the soil per season. Continually adding high phosphate fertilizer to your container grown or in ground planted plumeria the (P) buildup begins to sterilize the soil or soilless mix you're growing in. Our tests also showed a large portion of a plumeria(s) root mass was being destroyed.
The next issue;Another result of high middle number (P) over fertilizing is leaf chlorosis (leaf yellowing). Phosphorus is known to compete with iron and manganese uptake by roots, and deficiencies of these two metal micronutrients causes inter-venial leaf yellowing. It's my belief that many of the yellow leaf (chlorotic) plumeria seen by growers are suffering from indirect iron (or manganese) deficiency from over application of phosphorus i.e. high middle number (P) plumeria fertilizers.
My last thought on Phosphates;
Anyone who subscribes to the "high middle number" fertilizer routine for plumeria is helping to destroy our already fragile environment. As phosphate passes though your plumeria planting medium or any plant for that matter container or in ground and continues its journey destroying the natural bacteria and taking the "balance " from the top and sub-soil eventually entering the water table. This allows the phosphate to infiltrate water systems such as lakes, rivers and streams to pollute and begin killing other wildlife such as birds, fish and native water plants.
Now the potassium;
66 PPM is inadequate for most flowering plants as it has a very large role in the plumeria(s) health. We suggest a minimum of 250 PPM and a maximum of 600 PPM's. See the following explanation of how beneficial potassium is to your plumeria.
The following is a short description of what fertilizers do for your plants;
Nitrogen (N) aids in strong leaf and stem growth and promotes dark green leaf color. Too much nitrogen causes soft foliage and delays flowering, while not enough nitrogen causes stunted growth and leaf yellowing.
Phosphorus (P) is needed for root development and also helps the plants to set buds for flowering. Not enough phosphorus can cause stunted plant growth.
Potassium (K) improves plant hardiness in both hot and cold weather. It also helps in seed production and improves the size and quality of flowers. A plumeria fertilizer with not enough potassium will result in poor cellular structure therefore a weak plant, reduced flower quality and flower size.
Two must read Links:
http://www.angelfire.com/
http://davesgarden.com/
See our plumeria science pictorial: http://www.plumerianews.com
