thanks everyone, i grow outdoors in large pots. I use a mixture of peat moss, worm castings, bat guano, perlite,coco coir, compost,egg shells and kelp. The amount of bat guano I use is probably 10% of total. I have overdone it before and burnt plants but you learn from experience. This is not the mixture I use for seedlings, they would be in peat/perlite mix.