Is there any opinion on capturing the watering runoff and reusing it? During dry times, rain collection may be thin. If it is suitable, are there designs for a collection system?
I wouldn’t do it, but I live in U.K. so water isn’t that much of an issue.
I do try to use collected rain water where possible, but if you are talking about collecting water as it runs through pots, is there not a risk of salt and mineral accumulation? Would you be filtering the water?
As luck would have it, this is actually something we discussed with friends a few years back during a drought in the south of France… it never went to implementation because said friends didn’t have enough space to try it and I lived in an ‘agreeably moist’ part of the world.
In theory, you could add rain gutters to the underside of your shelves to collect the used water and direct it towards a pan in a solar still or a wick still. The still will separate the water from the soluble salts through the evaporation/cooling cycle with the salts being left in the pan. You can build such a still by slightly modifying a cold frame.
One issue is that I’m not sure of the still volume required to process the amount of water required for a large shelf or a more serious collection.