“Cold, dank cellar” sums up German weather, perfectly.The only time you need to box leaves is when the average relative humidity is low. It just allows the leaf to die and change color before it dries. If your RH is predicted to remain at or above 70% for a week or so, boxing is not necessary, just hang them as usual. All boxing does is maintain humidity until the leaf color changes to yellow or brown.
You'll need a box that is large enough so the leaves will fit into it without bending or folding. Line the bottom with paper or cloth, stack your leaf inside then cover with more paper or cloth, close the box and shuffle the leaves daily removing the ones that have colored and hang them to dry as usual. In short, it's just a way to maintain proper humidity until the leaf changes color.
Note that it's very important to check the piles of leaf daily or you may end up with a pile of rotten leaf. Piles of wet leaf can heat up quite a bit and start decomposing in just a few days, hence the importance of shuffling them daily. If your leaf was at least beginning to yellow on the plant before harvesting, all of the leaf should color nicely within 3 to 7 days. If it takes longer than that, then you probably harvested too early or maybe the temperature was too low.
I don't keep track of the final weight of leaf, but I estimate that I end up with about 2 ounces of destemmed leaf per LD plant, judging by the bulk.
Keep in mind that I live in an area that is generally very warm, if you're attempting this in a cold, dank cellar, you may not get the desired results. There is no 'one size fits all' solution to producing quality tobacco. You have to learn by experience what works best in your environment.
Good luck!
I’m expecting to have trouble with maintaining humidity after I harvest. Looks like containers and boxes might be what I need…