learning to water

Watering should be pretty simple, right?  Just train a hose on something like a mushroom log for a few minutes until it looks wet, then go home.  Well, that is what I did my first year mushroom farming.  Those logs turned out pretty well considering that this little water doesn’t really penetrate into the logs.  What you need in the first six months of mycelium growth – what we call “spawn run” – is a weekly or biweekly watering of about an hour of continuous watering.

I wised up my second year of operation and invested in a couple of sprinklers.  They both fit on the end a 5/8″ water hose and delivered water to between 20 and 40 logs at a time.  I balanced the sprinkler up on the log stack and turned the nozzle to start the water flowing.  Back then my logs were scattered in a few yards, but all close together, so I would bicycle over to each yard every hour to move the sprinkler.  For one yard this lasted most of the day.

My third year I bought a fancy new sprinkler on a tripod.  The tripod meant I wouldn’t need to balance the sprinkler on logs, and come back to a sprinkler that was spraying right into the ground.  This sprinkler also produced finer droplets, which watered in hard-to-reach places better.  It was a fine sprinkler, but I still had to move it every hour.  This took on a ridiculous cast after I introduced hundreds more mushroom logs and moved them to a central location at Grow! Twin Cities.  Yes, last year I would spend a day and a half at a time watering.  Fortunately this was largely unnecessary until midsummer, when the rains tapered off.  Then I started fantasizing about my next watering system, and I had lots of time to contemplate it.

That fall I purchased some micro-sprinklers, tiny sprinklers that work together in tandem so that you can water a larger area, and using less water.  I used standard hose, but with lots of complicated and expensive brass fittings recommended to me.  I attached these sprinklers to u-posts – green painted metal posts like you might use to hold up rabbit fencing or tomato plants.  But the sprinkler setup was expensive enough that I had only enough to water a hundred logs at a time, so I was still moving this around every hour.  Also it didn’t look so impressive.

Not like my latest set-up, which I put together this spring, and is doing well so far.  It is also a micro-sprinkler system, but the fittings are cheap enough that I was able to buy enough to outfit my whole operation.  Theoretically that means there will be micro-sprinklers among the woods log stacks as well as in the shade structure, but I haven’t tackled that yet.  I only have four or five micro-sprinklers on a line, and each line is controlled by a shut-off valve (see top photo).

individual micro-sprinkler on riser anchored with ground stake, connected to 1/2 inch poly tubing with 1/4 tubing.

These individual lines lead back to a whole series of components, including a water meter, 30 psi pressure regulator, filter, and backflow regulator.  Oh, and there are a couple of adapters and shut-off valves in there for good measure.  They all do their thing, but I was most anxious about putting in a pressure regulator, since the woods area is uphill and about 30o feet away, and there will inevitably be a loss of pressure.  So far all these fittings have done the trick; the micro-sprinklers work in the shade structure, and I have used my old tripod sprinkler to good effect in the woods laying yard.  This is all very good, but what watering system will I use next year?

the whole bloody series of watering components just outside the house where our farm pump is located

four wheels to the market

The Mill City Farmers Market is only a few miles from our house, so I have been bicycling over there on Saturday mornings. A friend is lending me his bike trailer, which is at least six foot long and has a capacity of 300 pounds. I am utilizing most of that, carrying fresh and dried mushrooms, mushroom log kits, table cloth, bags, and mushroom books.

My friends at Stone’s Throw Urban Farm have been generous in bringing my tent and tent weights with them, weight that would most certainly put me over the edge. Even so, I avoid hills on the trip to and from the market!

Here is my table at the Mill City Farmers Market, with log kits, shade tarps, books, dried mushrooms, and only a couple of fresh mushroom baskets.

pruning against mold

weeding/pruning forest floor stacks (new shiitake logs)

One of my most neglected tasks is managing the log stack environment.  It is important to finesse humidity and air circulation in order to encourage growth of your mycelium while discouraging molds and competing fungi.  Molds build up when you have too little air circulation and high humidity, and can inhibit mycelium and mushroom harvests.  Mycelium thrives on the humidity, but it can tolerate more air movement than mold.  Hence my recent efforts to improve air movement in forest floor stacks (above) and shade structure stacks (below).


landscape fabric controls grass in shade structure log stacks (new shiitake and oyster logs)

For the latter I put down landscape fabric, since the grass is so vigorous.  I’m hoping the forest plants will take longer to recover and I won’t need to do more than occasional pruning/weeding.  How did I think to make these changes?  Mold of course, which I found in sometimes generous swathes along the bark and sometimes at the log ends.  The good news is that most of it was white mold and that the mycelium also seems to be thriving, which I can see from the white sections on the log ends which line up to the inoculation points (below).  I’ve found a few logs with blue/green mold, which is more malevalent.  I try to isolate all moldy logs – since they bring up the mold counts for the laying area altogether – but I make a special effort with logs with blue/green mold.  I have a “bad children” pile for this purpose that is a hundred feet or more from the other logs.  These moldy logs can still be quite productive, but they won’t infect the others.


mycelium growth at log ends and corresponding inoculation points (new shiitake logs)

cool mushrooms

Last week I put together some “coolers” – boxes to keep mushrooms cool during the farmers market. The idea came from mushroom farm and spawn supplier Field and Forest Products.

I cut foil-backed bubble wrap to fit into a cardboard box, taped it in with foil tape and I was ready to add mushrooms and some ice packs on top. I used enclosed ice packs about the size and shape of ice cube trays – and they can be cut apart as needed. The ice packs sweat a little, so I kept a layer of paper bags between ice and mushrooms. However the whole setup performed admirably!

mushrooms love rain!

We have had a lot of rain fall in the last few weeks, and the mushrooms love it, especially the shiitake and nameko. I have harvested a two or three dozen pounds of shiitake, while my few logs of Nameko are also doing well, and oysters have fruited a bit too, though its a bit too cold for them still.  In general I’m appreciating the rain.


this is a gray oyster that grows reliably throughout the season


and here are some Nameko fruiting on Cherry wood. The slimy texture doesn’t endear my wife to these mushrooms, but the slime goes away when you cook them, and they have a firm texture and a delicious cashew-like flavor.