Growing with the Bag Method - Pt 2

After the implementation of the various corrections as noted in the previous article, the mycelium seem to be developing significantly more quickly and in line with the 10 - 14 day development period as outlined by other growers online. This is a promising sign that I will be able to soon reach my desired output of ~ 100 lbs a week grown from 80 lbs of dry weight substrate hydrated to around 220 lbs across 24 ~9lbs bags.

I have encountered a couple other issues that I have been thinking about related to the growing process, as listed as follows:

1) CO2 levels

2) Mixing the substrate well.

Regarding CO2 levels, I suddenly realized that during the colonization phase, large amounts of CO2 are emitted from the colonizing bags. I had approximately thirty 10-lb bags colonizing and I started to worry about whether the CO2 ppm would climb to dangerously high levels. Given this concern, I bought several CO2 monitors to place in the colonization room and other areas of house. When I measured the ppm, the grow room was at around 2000 - 3000ppm at around waist height (although maybe I should have measured at foot level as CO2 is denser than air).

However, as I continue to fill up the grow room, the ppm will rise if I have up to around a hundred bags colonizing at the same time. While colonizing mycelium enjoy higher CO2 levels up to around 10,000 ppm, if it were to exceed that, I would need to find a way to diffuse the CO2. I am not quite at that point for now, but it is just something to consider.

Another point of relevance with the CO2 levels is monitoring them within the grow room. By monitoring the CO2 levels during the fruiting process, I can ensure that the air flow is adequate and the mushrooms are getting enough oxygen. I'm not worried about this for now but once I bump up to max capacity, I am concerned that the lack of oxygen may produce suboptimal fruiting conditions as my ventilation is not as robust as it could be.

As for the substrate mixing, I noticed that some of the bags were colonizing more quickly than others and one bag in particularly suffered from seemingly slower growth (as opposed to all the others). While this is an overall promising sign that most were colonizing well, it begs the question as to why this one was slow. I believe that the substrate for this bag was scooped from a dryer part of the mix, and had less water mixed in. This severely stunted the mycelial growth. Therefore, I believe that I need mix the substrate and water more adequately before packing them into bags and sterilizing the mix.

One a somewhat related notes, I put in the bags that were not hydrated properly (to around ~30% instead of 60%) in the fruiting chambers to start growing yesterday and I was disappointed when pins did not quickly form. I realized that because some bags had up to a 1/3rd of the area not colonized, the mycelium, upon contact with more water, were prioritizing finishing the colonization process before focusing on fruiting. Since they had more nutrients to consume and expand into, that is there first order of priority.

This teaches me that I should never put in bags that have not been fully colonized. I just changed the fruiting room conditions to match the colonization room and will keep it as such for another week, but since I have already made slits in the bag, it increases the chance of contamination. In the future, I should always wait until full colonization. However, I should not have this problem in the future as long as I hydrated the substrate adequately, which should always be the case as long as I mix well.

In light of these other factors, I continue to realize that even the seemingly easy process of colonization and fruiting have their own difficulties. I hope to continue to refine my understanding of the process and have happy mushrooms fruiting soon!