I have mushrooms on the brain! One of the forums I read had a question about straw bale gardening, and it made a connection for me that I had not considered before. (A definition- straw bale gardening is a method of amending poor soil the slow, natural way while still allowing you to grow food the first year. You turn straw bales so the straw runs vertically, soak them well, add some live compost spread on top or dug into depressions in the bales, and plant starts or seeds directly in the compost. The plants grow and help to break down the bales, and in one or two years depending on your climate, the straw has turned into nice good soil and even conditioned the soil beneath it – i.e., 12 inches of straw worked this way will give you 18 inches of good nutritious soil after decomposition.)
- Plants will grow in straw bales, given some nice live compost to start them off
- Wine cap stropharia (Stropharia rugosa-annulata) and beech (Hypsizygus ulmaria) mushrooms will grow in straw. You most often see this laid out flat on moist ground… but if the oyster will grow on straw soaked and stuffed into cardboard boxes, and these two species have similar habitat requirements, it’s plausible they will also grow and produce in bale format. Stropharia needs some soil bacteria to really get it going and fruiting well, and the scoop of compost required for straw-bale planting should be perfect for that.
- These two mushroom species have been shown to increase the growth of annual vegetables planted in the same bed, by digesting the mulch material on top of the bed and sharing its nutrients with the vegetables via partnering with their root systems (See Mycelium Running by Paul Stamets – available on Google Books)
I wonder if inoculating the straw bales with spawn of either of these two mushroom species around the time of planting would similarly have a boosting effect? Perhaps even removing the need for additional nutrients later on, if the timing is right and decomposition of the bale is at the appropriate stage? Stropharia spawn is often sold in pegs, so it would be easy enough to hammer into the edges of the bale for good colonization. It would likely speed the decomposition of the bale, but I don’t know if that would be good or bad – depends on whether the mushroom mycelium could finish off the bale before the plants froze for the winter…
I might have to try this. I have one bale of oat straw saved over from last fall, but I’ve already ordered the Oyster spawn to set it up as a cardboard box (or reusable plastic tub) farm. Must remember to stock up on straw this fall!
Hah – checking back at some of the initial straw bale articles I had bookmarked long ago, it turns out using mushroom spawn is not a new idea – and the initial scoop of compost (containing active soil bacteria) was meant to kick-start the decomposition of the bale and make its nutrients available to the plants within, eliminating the need for future nutrient addition. I still think it would be interesting to measure the effect of these saprophytic plant-growth-boosting species on the whole shebang, though… and definitely their presence is a good addition to the garden beds you’re creating by composting the straw bale in place!