Weakly weekly..?

[Jasonmc89]

I have always been confused by the very popular "weakly weekly" method of fertilising.

The reason is because I don't know what the fertiliser is to begin with. Some fertilises have NPK number of 20-20-20, while some, such as Orchid Focus Grow have the numbers 2.2–1.2–2.1.

So is it the case that the Orchid Focus fert is already about 10 times weaker than the typical balanced 20-20-20 one?

It seems to me that an orchid grower using the weakly weekly method with a balanced 20 fert will be feeding their plants a stronger feed than I would by using the Orchid Focus fert and full strength or even higher!

Is this correct? Or does it not really work that way?

The reason I'm considering trying his method is because I think a few of mine are showing signs of over-fertilising, even though I stick to the Orchid Focus's recommended doses.

Help me.

Thanks.