Posted by Candace Hess and Cathy Scott on August 24, 2016
Mushroom logs require patience. But if it has been close to a year after the plug date on a log, and there is no growth, it is time to take action. Shocking your logs will wake up your Shiitake logs within a week while Oyster logs may take up to one month.
This log gave us a big surprise by fruiting at the ripe, old age of 9 years!
When do I shock my mushroom log?
Spring and fall are the best times to shock Shiitake and Oysters. Summer can be a bit hot but it never hurts to shock a few times to force more flushes from your logs. The only time you don't want to shock you logs is when temperatures will dip below freezing.
The easiest way to shock a log is by knocking one end of the log sharply on the ground to "wake up" the log, and submerging them overnight in cool, non-chlorinated water overnight. Here at Everything Mushrooms, we have a large trough to fill with a pallet of plugged logs. The bathtub, a large trash can, or even a bucket will work just fine as long as the log is completely covered. We noticed pinning the very next day after shocking our May 2015 batch of Shiitake plugged logs!
See the little, baby Shiitake pushing wax out of its way!
After logs have been soaked, store logs so they have plenty of air and room as they grow. Most importantly store them so it is easy to see fruiting mushrooms. It is a good idea move logs close to the house or near your walking path to the door so you won't forget to keep an eye on them. We lean logs against a fence, so with a quick glance, we can see any new growth on all logs.
Stacking in a log cabin formation is good, just be sure you can see through the middle for any hiding mushrooms. Keeping logs off of the ground will also help keep the bugs and slugs off of the mushrooms as they fruit.
What do I look for?
Baby mushrooms will appear as white or brown bumps anywhere on the log. The little mushrooms will sometimes push out the wax, or even in between plug holes to push the outer layer of bark away from the log. It is alright to peel away bark to help a little pinning body to appear with less effort.
Shiitake caps are noticeable just two days after soaking our logs in water.
We have young Shiitake mushrooms fruiting just 4 days after shocking.
How can I get more mushrooms from my log?
Give the logs a break of a few weeks before shocking them again. Watering during fruiting can increase the yeild and overall health of the mushrooms on your log.
Check the mushrooms daily, if they seem dry they probably need a drink. Simply taking the hose to plugged logs is perfectly fine, just be careful to have low water pressure on the delicate mushrooms themselves. However, putting them under a misting system would lead to slugs and mold. Watering logs in the morning and at night during fruiting can't hurt! If it is dry in your area or you haven't had many or any mushrooms for a while it is probably due to dehydration. In this case, you will want to give your mushroom logs a thorough watering every 1-3 days after they have been soaked.
If you live in a dry area it is a good idea to give you logs a drink periodically year round. My rule of thumb is to give my logs a good hose down when it is cold enough that most of the precipitation has been in the form of ice or snow in the winter. Any other time of the year, I water my logs when it is dry enough to be watering my perennial plants.
What other ways can I shock mushroom logs?
Shocking logs mimics natural signals that tell fungi it is an advantageous time to fruit. The most commonly used methods for shocking are a physical trauma, rapid change in temperature or an increase in moisture. Like plant flowering, mushroom fruiting can actually be a stress response. A last ditch effort to have genes survive in the form of spores under adverse conditions like coming to end of its food source (a bag or log full of mycelium).
I like to think the physical trauma imitates a lightning strike or a tree crashing to the ground. In nature this would signal there is fresh wood for the colonizing. signaling the fungi to make mushrooms to ride the wind or a bug to a fresh new home.
Rapid change in temperature is a good way for fungi to tell the changing seasons. From winter to spring or summer to fall both offer the best temperatures an good rainfall for mycelium growth. Professional growers move logs inside and out for a good temperature shock.
Increase in moisture induces fruiting by imitating a natural rain event. Finding a happy moisture medium for everyday growing and mushrooms can be a bit of a challenge. I tend to lean toward the side of keeping the moisture low. After all in nature you will have times when mycelium will survive very very low moisture conditions. When things are too wet it invites all kinds of invaders. Keeping the moisture/humidity low also allows for a big rain like signal that will induce fruiting when you do soak overnight. However, if you live in a dry area or you haven't had a flush of mushrooms for a while it could be due to not enough water. A day long soak with continued, daily watering should do the trick.
Keep in mind many mushrooms only fruit at certain times of the year, no amount of shocking will get them to fruit. For shocking stick with Oysters and Shiitake. For all mushrooms logs, consistent watering during the dry months, and snow packs in the winter will keep your logs ready to flush each Spring/Summer/Autumn for years to come!
Remember: NEVER give up on your logs! This log was plugged with Shiitake 7 years ago, and fruited after shocking this Spring!