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question on cuttings

i waxed many cuttings and put them in plastic bags and stored them in the frig. i noticed a small amount of condensation on the inside of the bags.  Is this a problem. since the ends are waxed, i would think that they could survive the condensation. Or should i spend $199 on a food saver??

Condensation is not good. 
If you put a piece of paper or similar in with the cuttings it will absorb the condensation. 
Also it helps if you let the cuttings air dry after washing them before sealing in a bag.

The food saver bags are gas impermeable and don't let the cuttings breathe, they will eventually "pickle" the cuttings during storage. The small amount of oxygen in the bag will be used the cuttings and they will suffocate, then bacteria that do not need oxygen (like the type used to make yogurt and pickles) will begin to digest the cuttings and causing the bag to puff up with CO2. It is a no-go, cuttings are alive and still need a small amount of oxygen for biological function for their metabolisms: respiration

The solution to the condensation comes from understanding the different facets of the issue:

1. Condensation forms due to a differential in temperature, it is a simple concept but becomes complex when talking about cuttings. Think of a cold drink on a hot day, condensation forms on the outside of the cup from water vapor in the air contacting the cold surface and turning back into a liquid. That is simple.

2. Now think of cuttings in a bag, when the bag is put in the fridge the bag itself becomes colder than the air inside for a time, causing condensation on the inside surface of the bag (like condensation sometimes forms inside windows in winter). Next, when the temperature of the air inside the bag gets warmer from opening and closing the fridge, adding warm foods, taking the bag out, the fridge cycling etc. any more humidity given off by the cuttings will condense on their surface because they are colder than the air.

3. The cycle repeats until there is a pool of water collected in the bag (which can help mold and bacteria to grow) and the cuttings have dried out. 

The solution: to stop water vapor from leaving the cuttings, and condensation from forming on their surface they need to be wrapped tightly in a gas permeable plastic (plastic wrap or normal plastic bags). Now, when the air inside the bag warms condensation can only form on the outside of the plastic wrap, because there is no air in contact with the cuttings themselves. And without the cuttings giving off water vapor less condensation will form inside of the bag overall, and the cuttings do not dry out. It has been done by members here for many years because it works, it is just not explained often. Wrapping cuttings individually is best, but the small amount of air left when wrapping a small bundle will only cause a small amount of condensation to form and still prevent the cuttings from drying out.

p.s. If you don't want to wrap the cuttings... leave the bag open when you first put it in the fridge, then close it after the cuttings have cooled. This prevents most condensation from forming during initial cooling, but the air inside of the bag will still allow moisture to escape from the cuttings and condense when the bag warms/cools as described above. Keeping the bag in the crisper will help minimize that because it stays a more constant temperature than the rest of the fridge. You should periodically remove water from the bag if it builds up enough to be getting the cuttings wet, take them out and quickly wipe them and the inside of the bag down dry (setting them on the counter when they are still cold will cause them to become wetter, like a cold drink on a hot day) and then put back in the fridge (with the bag open at first remember).

Thanks Chuck, sorry to hear about your cuttings, I know the feeling.

Thanks hoosierbanana really helps me in understanding.  
this is so important for fig cuttings storage. 

thanks men, you saved me $199. just finished wrapping with scott towels and bags.  hoosier, i like bobby knight, Chuck, stay warm.

Brent ( Hoosierbanana) knows what he's talking about. I agree 100 percent in his findings, both theoretically, and in actuality. Thanks, Brent, for your incite, experience, and overall knowledge.

Ditto to Bill's remarks... great info, Brent! Thank you...

Where does the common wisdom of keeping cuttings moist when storing in the fridge with a slightly wet paper towel inside a ziplock bag originate from? I believe it's from the practice gathering fruit tree scion wood for spring grafting.
Fig cuttings are different. Thanks. hoo!

The fridge I have for cuttings in the garage is over 20 yrs old and I'm not so sure about the "crisper" drawer in it, as my past experience is that it dried some of my cuttings to a crisp. This year I need to keep some cuttings Oct to March so after wrapping I put them all in another sealed bag and in that one I put a wad of damp newspaper. So the damp paper does not contact my cuttings but hopefully satisfies the thirsty cold air. I check every so often to make sure no mold is forming.

I'm curious. If properly wrapped in damp paper towel inside a zip lock. How long should cuttings generally keep as viable? I've never stored my cuttings...Just planted them right away. Unfortunately I'm running out of window space to root them off season.

The technique for storing apple scion wood is the same as figs. Usually apple scion is smaller in diameter than figs. There used in grafting more than rooting I believe. I think the storing moist cuttings came about from the next process. If you have these moist storing conditions and raise the temperature roots will start. I believe as long as the cutting remains dormant, moisture loss is minimal. It seems like the majority of people are worried more about cuttings drying out vs molding. I just opened some cuttings I stored dry over a year ago. I had more mold issues than drying of the wood. Even some that looked very dried out still had a green under the bark. I just stored these to see how they would look. I'm going to see if they will root in a few weeks just for fun.

The cuttings stored with damp paper towel molded first.
I also tried shrink wrapping them. The cuttings that were air dried were good. I stored a few not all the way dry after cleaning. Just patted dry. These ones didn't seem to last as long. I think after you clean your cutting keep them cold by placing them in fridge to air dry is a good idea.
This year I'm going to try dry newspaper wrapped around each cutting, in a zip lock after there dry.

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