Hi there, at KultureShock we generally use anywhere between 1000-1500ppm for the quick basal dip method or 300-600ppm for misting the plant.
Is that for orchids, or woody plants?
I know that using standard powder dips that work great for the latter, will damage orchids. Rootone F, for example, is 570 ppm IBA, 330 ppm Methyl-NAA, and another 800 ppm naphthaleneacetamides.
Our paste's are in the 80 ppm range because they get released slowly into the plant but for quick dips and misting I find a quick application of a higher concentration followed by a rinse works best, but i'd go with the lower concentration of 40ppm that the other board members are using if they are reporting success, It will save your hormones at the very least.
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