Stropharia Mushrooms on straw: instructions for use

Stropharia rugoso-annulata is an very tolerant and easy-to-grow species: an absolute must for mushroom lovers. It is known for its highly resilient spawn and can survive in patches for many years when inoculated under suitable conditions. The spawn can be kept up to one year in a fridge at 1-3°C, which is an extremely long time.

 

Option 1: in horizontal growing bed

Requisites:

  • 2 liters of Stropharia spawn
  • 50 kg of dry straw

 

 substrate straw selection and pasteurization for Stropharia

1. Substrate selection & preparation : choose good quality straw from the last harvest. In these drawings, we have drawn some kind of tub, but it is also perfectly possible to dig a trench in the garden and put the stropharia in the garden bed in the same way as drawn in the example.

keep the substrate in hot water (between 60 and 65 °C) for ½ hour. Let it drain and cool down to more or less 20 °C on a clean surface. If you can get to some CaCO3 (chalk), mix in 1-2% to rise pH a little. If you put the spawn before the substrate has cooled down sufficiently, the spawn will die from the heat and you are sure to get only molds. If the straw hasn’t sufficiently been drained, it may rot at the bottom. The moisture content of the straw should be 70-75%, i.e. when you squeeze it very hard, you will get out a few drops. Put disposable gloves before touching the pasteurized substrate, in order to prevent recontamination.

 Inoculation of Stropharia on straw bed - enten van Stropharia op stro

2. Inoculation: mix in the spawn with the straw. Make sure you  fill a horizontal container/bag or a bed in the garden with a number of 5 cm thick substrate-layers, between which you put a fine layer with dots of spawn, as if you were making a lasagna. Press well, in order to make intense contact between spawn and substrate. Don’t make the beds/bags thicker than 40cm. A 10-liter portion of Stropharia spawn (= 5 kg) is sufficient for the inoculation of 200 kg of wet material. You should mix in about 1 to 2% of Stropharia spawn.

preparing the stropharia bed

3. Incubation: keep the substrate bed safe from disturbances, protected from direct sunlight and keep it humid e.g. by means of a garden hose with spray-nozzle or putting a 3-5 cm thick layer of soil on top. Make sure it does not dry out at any point during incubation. Temperature may vary between 5 and 20 °C. It is not essential to put soil or plastic cover, but it protects and humidifies better.

first flush of Stropharia Mushroom on straw

4. Fructification: mushrooms will appear in maximum 4-5 “flushes” or series, with intervals of 2-3 weeks. The total yield is 10 to 20 % of the original weight of the wet substrate. Stropharia spawn can come back for years on end, as long as they get supplied with fresh layers of wet straw and as long as the climatic conditions did not kill them, such as extreme cold or inundation.

 

Option 2: on a straw bale

Requisites:

  • 1 liter of Stropharia spawn
  • One 25-kg straw bale

 

raw material selection mushroom cultivation in beds on bales

1. Substrate selection & preparation: choose good quality straw bales from the last harvest. Put the straw bales on the ground, into your garden (keep them rat and mouse free). Sprinkle them for a few days until they are completely soaked. The moisture content of the straw should be 70-75%, i.e. when you squeeze it very hard, you will get out a few drops.

Inoculation of stropharia on straw bale

3. Inoculation: mix in the spawn with the straw. Insert small balls of spawn on all sides of the bale, every 10 cm, as deep and as spread out as you can get it. Make sure there is intense contact between spawn and substrate. A 1-liter portion of Stropharia spawn (= 0.5 kg) is sufficient for the inoculation of a 25-kg straw bale.

Incubation of a straw bale with stropharia mushrooms

4. Incubation: keep the substrate bed safe from strong disturbances, protected from direct sunlight and keep it humid e.g. by means of a garden hose with spray-nozzle. Make sure it does not dry out at any point during incubation. Temperature may vary between 5 and 20 °C. It is not essential to put casing soil or plastic cover, but it protects and humidifies better. If you are using larger bales, make sure the ambient temperature does not rise too much, or the spawn will overheat at the center of the bale and die.

Stropharia oogsten op strobaal

5. Fructification:  mushrooms will appear in maximum 4-5 “flushes” or series, with intervals of 2-3 weeks. The total yield is 10 to 20 % of the original weight of the wet substrate. Typical Stropharia behavior is that they only grow on horizontal surfaces, so they won’t grow on the sides of the bale, but on top.