i started using this soil about 3 months ago, bio-bizz have been setting the tone for a while now. for my soil grow i thought id use this product,and the results were very good.i personaly thought i had took a risk by using bio-bizz all mix from the start of germination. the boys from the netherlands had recommended that i use starting- mix for seedlings e.t.c, then switch to all- mix once they are ready to transplant at a few weeks old. but i deciced to just keep them tucked up in the all- mix from start to finish. i didnt feed them fertilizers until 3 weeks old, and had no problems concerning root-burn or other side-effects.now my babies are 5 weeks old, and very bushy,compact, and lushious. i think this medium is a very good performer, although at the same time i was using some cheap B&Q house plant soil which also performed well on the same phenotype> overall i think it is worth the extra pounds, the worm castings,pre-mix, and other high-grade ingredients are not something you get in the local B&Q... excellent for perrenials, and shade loving plants...