Pecan shells?

[Tsepina77]

I asked this in the newbie forum b4 I found this one Can pecan shells be used in potting mix?

people use lots of things, wine corks, stryo bits, lava, horse manure but it depends on the type of orchid . my opinion if you are including pecan shells in small quantities you could try it but i know for a fact you should stay away from black walnut and their kin they have toxic effects on many plants in general.