Reply To: Organic soil Kisetsu-en Shohin Bonsai Europe › FORUM › Q&A › Organic soil › Reply To: Organic soil 23. January 2022 at 15:05 #59532 Geoff HobsonParticipant I am using Akadama/pumice 60/40 this year, there is no organic material in it and I have never added organic. For young plants I sometimes use an ordinary potting compost but only for young trees that are being grown on.