I agree Alberto, with the exception that a very free draining mix may be given a much more stable moisture content by adding a small proportion of moisture retaining ingredients. Peter (UK) On Tue, Oct 30, 2012 at 9:40 PM, Alberto Castillo <ezeizabotgard@hotmail.com > wrote: > > > > Coir, peat, and fines like fine sand, pumice fines or perlite fines are > extremely water retaining and wil not release it readily. No problem if you > can adjust your watering to their properties but if your bulbs are exposed > to rainfall it will be a disaster. > >