louis14

Many thanks to all for the much appreciated comments.

1/This is a plantation, we aim to make a profit, no just spend and spend. The 300 micron LDPE lining, if pierced will become unusable for any other project when it is guaranteed to last 25 years, so it would be an expensive misuse to pierce it. Much simpler for us to prod into the sawdust, without moving the corms and check humidity levels before and after watering.
I have miles and miles of irrigation pipes, that has taught me that the way to save large amounts of cash is to re-use, recycle, which requires planning and non destructive practices/uses when possible.
2/ We are 100% off the grid, so boiling water, only over a fire! Not so practical! That is why we use either bleach or KMnO4, which we used on all the corms in the first three boxes.
3/ We learn by trial and error but we are not in laboratory conditions. If all first three boxes fail in one month or two, we will revise and improve our method.

(I used to pick, weigh and count nematodes from a Kg of sand kept in formalin to evaluate biomass. It was done using a binocular microscope. Precise marine lab work it was, were it not for the fact that the samples had been dredged in a less than scientific manner).