Thanks Joseph - hopefully there will be some progress to post about :-).
And thanks for the info on the silica.
In relation to light my location does not currently have much to offer - and it just gets worse the coming months (Denmark is at 56° N - which is north of Newfoundland) - so I have bought some readily available LED "growth" lamps.
However, the I. alba (3-4 weeks old) and Dioscorea alata (also in the the Convolvulaceae family) below have so far survived/grown solely on light from a westerly oriented window.
