Mold question

[Needmorebrush82]

For the first time I have 3 rm18 trays in my nut fridge containing dco's that were started for a couple of weeks and then put to sleep. I have around 300 acorns in ziplocks for spring growing in January. Keeping the 18's moist has turned the fridge into a humidity pit. My acorn filled ziplock bags are slowly collecting moisture and slight signs of mold have appeared. Wayne had mentioned on the chestnut thread to poke a few holes in the bags and it would prevent mold. The chestnuts are all indeed mold free by using this method. I have had damp paper towels in the other bags without holes and noticed a tiny bit of mold on the paper towels. I took all of the paper towels out and added red cedar shavings instead of sphagnum moss as it is naturally rot resistant and I have it. I also poked a few holes in the bags to increase airflow. The nut fridge is maintaining 70-80% humidity so I don't think the acorns will dry out with monitoring. What do you guys think? I have never had so much moisture in my fridge but I am thinking this should allow me to increase air flow without drying out my acorns and prevent mold. Am I correct? Opinions wanted good or bad!

 

[yoderjac]

I'm not sure I have a good picture of your setup. I'm not sure I understand the 3 trays and 300 acorns. I'm also not sure about what you are trying to accomplish.

Chestnuts require cold stratification for 60 to 90 days. This is a combination of cold and moisture. Yes, getting the moisture content can be difficult. Holes in the bag don't prevent mold, they just decrease the moisture content. Not enough moisture and stratification slows or stops. Too much moisture speeds mold growth.

Acorns may be different. Some don't require cold stratification to germinate others may. It depends on the oak species. For those that don't require stratification, the objective is to simply delay top growth until a convenient time. That may be just a couple months if you plan to grow them under lights indoors, or all winter if you plan to direct seed in the spring or grow them outdoors.

To delay germination, you don't need high moisture content. They do need to be hydrated before storing them. You don't wan them to dry out in storage, but you need very little moisture to prevent this.

Another technique that is used for some oaks that germinate in the fall is called vernalization. With this method, you allow the nut to produce a root radicle in the fall and then plant it in a RM18 or 32. You water them normally and the water drain. You then place the entire tray in an XL ziplok bag and place that in the fridge. The humidity will stay in the bag, not increase the humidity in the fridge in general. Every few weeks check the try and see if they need watered or if they are still damp. The idea here is to allow the root radicle to begin growing over winter just like in nature, but the cold environment keeps top-growth from beginning. This places these seedlings at a little advantage over the other method that delays root radicle growth since the radicle will grow and prune. Once you take them out and they warm up, top-growth will take off quickly.

I find that placing them in the medium rather than on-top helps slow mold. This is true for vernalization or if I delay germination and then plant them in 18s under lights.

The XL ziplock bags are not closed for vernalization. This allows enough air flow that the cells dry out slowly in the fridge. They don't need watered unless the cells begin to dry out. I think I may have taken my DCOs out and watered them once or twice last year.

Hope this helps,

Jack

 

[Needmorebrush82]

Problem solved guys.

 

[Needmorebrush82]

I cleaned the acorns that I had doubts about with warm water. I added some shredded red cedar which is naturally rot resistant but also allows more airflow around the acorns. I also poked a few holes in the zip locks to ventilate them a little better and the mold has not been an issues since. Last year I had roughly 600 acorns in the fridge but I did not have planted trays in the fridge so moisture was not an issue. Thanks for taking the time to help!

 

[Needmorebrush82]

Oklahoma