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Chemical or Algae based fertilizer

Discussion in 'Orchid Culture' started by greenthumb, Oct 13, 2022.

  1. greenthumb

    greenthumb New Member

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    I don't know the specie of my orchid but I want to fertilize it. I own just 1.

    I have a 25-10-10 PlantFood Orchid Fertilizer. I bought my orchid from a reputable place like 2 months ago and it is in sphagnum moss as substrate. I think there is no ''food'' in the pot. I want to fertilize it but I don't know how much to dilute. It says '' Mix 6ml of fertilizer per 5L of water. If I dilute it for 1 litter it will make a really small quantity to calculate and put.

    Should I use algae based fertilizer since I've read that it gives better results and there is less chances to burn the roots?
  2. Ray

    Ray Orchid Iconoclast Supporting Member

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    Oak Island NC
    From a chemical standpoint, it doesn’t matter the source of the ingredients, the ions absorbed by the plants are identical.

    The claims made by manufacturers and sellers can get confusing. For example, there are products made from kelp that have been processed in a way that has degraded the more complex phytochemicals and rendered them no better than a fertilizer, yet they are claimed to be more than that. Then there are other products made from kelp that have been passed through a process carefully designed not to degrade them. They are excellent growth stimulants, but not fertilizers (although folks sometimes think they are).

    As far as dilution of the fertilizer you have, it’s going to depend upon the frequency of feeding you wish to do. I have found that 75-125ppm N is a good concentration for plants fed weekly. If you divide 9.2 by the percentage of nitrogen in any fertilizer, the result is the ml/L for 100 ppm N, allowing you room to round up or down for measuring convenience. Your fertilizer, therefore, would require 9.2/25=0.368 ml/L, or 1.84 ml/5L, and I’d just round it up to 2ml.

    If you feed every 2 weeks, double that, and if you feed twice a week, halve that.