When it became a bit warmer again I put my mint plant outside after it stayed inside for the winter. However, after I came back from a short vacation, almost all leaves turned black. I don't know what is wrong...
Also there are white grain-like, chalky thingies in the soil. They are not stones, if I take one and squeeze them they pulverise and it is like chalk. Can this hurt? What is it?
Can it be that the transition from inside (~20˚C) to outside (~8˚C at the time) was too sudden and it died of cold? What could I do now to save it?