Advice on Fertilizing?

[SouthPark]

Originally Posted by orchidlauren

Wow! They’re very beautiful! Wish I could do that here!

I wish that you could or can too! What I find quite excellent is that you and other very keen growers do remarkable work with growing your orchids with various encountered constraints. We can all learn from your shared experiences in this orchidboard forum.

[richardb]

Like Ray I fertilize at every watering. I use a combination of Peters commercial (not orchid) fertilizers according to season and adopt the regime of "weakly weekly" which gives excellent results.
I understand the need to dilute ordinary garden fertilizers to maybe 1/2 or 1/4 strength but have never understood why people do that with specific orchid fertilizers. Much research has gone into those special potions so surely the instructions on the bottle should be followed.

[Ray]

Originally Posted by richardb

I understand the need to dilute ordinary garden fertilizers to maybe 1/2 or 1/4 strength but have never understood why people do that with specific orchid fertilizers. Much research has gone into those special potions so surely the instructions on the bottle should be followed.

My logic for using very diluted fertilizer is because the plants have evolved receiving solutions (rain) of VERY low solids contents and electrical conductivity, very frequently, so it makes sense to follow that in cultivation.

The ingredients used in "orchid" fertilizers and general-purpose garden fertilizers are identical. About the only difference is the label. Don't forget, a fertilizer manufacturer's goal is to sell fertilizer, not help you grow better plants. The "research" that goes into designing a formula is "what did the customer ask for?" or "can we make a generic formula that will suffice for more of our customers?", as switching is costly in a manufacturing operation.

About the only formulas I'm familiar with that were backed by university research are Miracle Gro Mir-Acid by Dr. O. Wesley Davidson at Rutgers 70-80 years ago, those originated at Michigan State University about 15 years ago, and K-Lite, derived from an MSU formula by one of their researchers. All were designed "on paper", with the mineral ratios based upon research into the needs of plants with some orchid-related assumptions, and in all cases the evaluation was the same: "We tried it and it worked".