Q. Which book of the Mittleider gardening books gives the best-detailed instructions on using irrigation water with grow beds? I have seen some pdf files on basic set up for grow beds, the last thing I want to be doing is unplugging clogged holes several hours a week. Can irrigation water be used in all circumstances, do you need a certain amount of psi?
A. Probably what follows is more detailed than in the books.
Irrigation water can be used in the automated PVC watering system, but care must be taken to filter the water before it goes into the pipes. The stronger your pressure, the fewer problems you’ll have and the faster you can water your garden, but we sometimes water with only gravity pressure.
In addition to sand, etc. plugging the pipes there is the risk of small weed seeds getting into the garden. For this reason, it is a good idea to filter irrigation water if possible, even when using it directly on your beds or boxes.
In the Foundation’s Zoo garden in SLC, Utah we filter the water from the creek right as it enters the 2″ flexible hose from which our Honda 5.5 hp pump sends it into the garden. We use three levels of filtering, very coarse to stop rocks, etc., medium to stop pebbles, and nylon hose for the finer particles.
Regardless of our best efforts some things still get through. In the beginning, I kept a couple of awls handy and (too often) would resort to reaming out the holes. With over 100 beds you can imagine this could be a BIG job!
We soon discovered that you can open the end of the pipe for a few seconds, close the end, then tap on the pipe with a hoe or rake handle while the water is on. This almost always clears the obstructions. And it is a good idea to open the end a second time AFTER tapping on the pipe, thus letting the debris you’ve dislodged wash out also.