Ai’ve been catching rain in earthworks (not accessable for drinking) and some in buckets from roof runoff for a while now. Ai’m wondering - could water be caught in small (or not so small) containers (for drinking), without a roof or earthworks? and if so, what in? The best ai could think of would be emptying out wild gourds and sticking dry grass stems in the holes at the tops, in a funnel shape and putting them out in the rain. Would that collect a significant amount of water? How long could such a thing store, without rotting?
In the desert southwest near Tucson and Phoenix you can still find barrel cacti that have been sliced in half to form natural rain water caches. It’s pretty awesome. They don’t hold a lot each, but if you have several in an area it forms a series of bucket-fulls. Also, I’ve hear that in northern Arizona indigenous people would bury clay vessels filled with water in order to protect against future droughts. If the vessels are properly fired, then that might work in any climate (but not really a cache system).
Thats cool. Ai dont really live in a place with barrel cacti, though. 
Think just putting out a lot of wide bowels would work?
as an aside, i’m pretty sure drinking rain water has the same problems that drinking distilled water does, no minerals. 
These minerals, can they be added to rainwater by making a tea, perhaps with nettles, or some such thing? What minerals do I need that water generally provides for me?
I’ve been catching rain in a tarp for awhile and making herbal teas over a fire…don’t know if they have alot of minerals though… ???
Mainly Magnesium, Calcium, and Sodium, but I think you can easily satisfy mineral needs without water. The problem is mainly the lack of any kind of dissolved material (it is “hypotonic”), which plays havoc with cells, and can leach minerals from bones/teeth and draw away electrolytes.
The concentration always strives to be equal throughout the water.
If the water inside a cell has a high concentration of minerals, but the water outside has a low concentration, the water will flow into the cell in an attempt to dilute the interior concentration to that of the exterior water.
Distilled water has little to no dissolved material, though, making it next to impossible for equilibrium to be achieved. The water flows into the cell until it bursts.
This is why nasal spray, eye drops, hydration IV’s, etc, all use saline solution. Distilled water will hurt your eyes/nose. Even tap water can be painful, but mixing some salt in will, somewhat counter-intuitively, prevent this.
So the short answer would be: Tea or soup is fine. Or just drink with food.
Rainwater isn’t as pure as distilled anyway, because in order to condense and fall, it needs particles to condense onto.
Easy to demonstrate: in 4th grade, my science teacher collected freshly fallen snow in a clean white bucket and sealed it. Coming back from the weekend, a tiny amount of ‘dirt’ had settled on the bottom.