They have to be very careful to cover fruit with plastic bags, lack of air can cause mold problems.
There are paper bags used to protect grapes or peaches against fruit fly or birds and are of different sizes, which can be used in different fruit (these paper bags are not destroyed if it rains).
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I have wondered about this too- apples baking inside a plastic solar oven for many months. Zip Locks and bread bags would have to be “food grade” plastic but I still wonder about off-gassing chemicals.
Food grade plastics do bleed certain chemicals such as the synthetic estrogen I mentioned. I do not know the state of research on the subject but there are people studying this issue that believe the synth est. may actually already be having a strong effect on young men, reducing their sex drive and creating less incentive to start families- this from estro. bleeding from food grade plastic used for packaging. I’m not saying this is a genuine concern, but for those simply trying to reduce their intake of synthetic chems it seems reasonable to question the use of a method that has not been studied for possible health consequences. Day after day of sun exposure certainly breaks down plastics.
As it turns out, obtaining microperforated ziplock bags isn’t as easy as I had hoped. Alternatively, has anyone tried using a derma roller to make their own perforated ziplock bags? For example:
Any tips on what size needle might be most suitable?
I also looked into bread bags. You can buy microperforated bags about the size of a sandwich bag, to use on individual fruit (used commercially for small pies and quiches) but I could not find any with drawstrings like in Acedo’s photo. They are actually designed to be heat sealed but as far as I can tell it would be very tricky, if not impossible, sealing the tight section closest to the stem, between fruit and branch.
Leaching plastic is a sobering thought. If that’s the case, perhaps paper is the best way, but I do like the transparency of plastic, much easier to monitor.
Somewhere here is s post where Bill had a template with nails I believe to make zip locks with holes.
Ziplocks caused my grapes to rot while Organza bags did not and kept the fruit perfect. No apparent difference between the 2 for apples although the Organza bags were easier to install, allowed to tie string to branch to reduce windfall losses and looked way better than a tree covered in plastic bags. Hopefully I will have pears and plums to experiment on next year but so far in my zone 4 but hot humid summer climate the Organza bags are winning. See my post under apples as well as at the end for grapes for photos: My Backyard planting experience (Part 2) - Zone 4a/b Quebec, Canada - #3 by hungryfrozencanuck4b
Another option is these purpose-made polyethylene drawstring bags:
Not sure if they are any different to organza.
Here is another source for the polyethylene bags. They come in several sizes and are heavy duty so they should last several years. Since they are mesh they can’t keep fungus and bacteria out but they should block most bugs.
http://r.ebay.com/UDlQHc
I ate the apple before I took a picture of it, but this year one of my apples had the red imprint of ‘Ziplock’ on it from the sun. The ziplock freezer bags have a negative imprint of the brand on the outside of the bag. The effect was kind of amusing and lead me to think that if done in a controlled way could be used to imprint branding for various companies on the surface of the fruit.
Reporting back, I tried both the polyethylene drawstring bags as well as using a dermaroller to perforate zip lock bags.
The polyethylene drawstring bags were so-so. Despite the drawstring they are hard to seal and lack the convenience of zip lock bags. A bird or possum also tore a hole through one, although they designed for stopping insects rather than bigger creatures. Despite all this, they managed to save about half of my cherries (cherry season in Australia right now).
The derma roller was useless, not sharp enough to properly puncture through the zip lock bags.
My next effort will be attempting to use a sewing machine to perforate ziplock bags en masse, not exactly sure how yet, never used a sewing machine before. (I’m hesitant to puncture with nails due to the size of the holes, although I suppose with apples one cuts entire corners off the bags). Any tips appreciated.
The problem I had with punching holes with a nail was that the hole size gets smaller as you remove the nail. These holes will allow water to eventually drain out but moisture/humidity remains high in the bags. For me drilling the holes is much better at removing humidity.
Thanks Auburn, I’m willing to try it. A few questions:
Are the drilled holes small enough to keep out oriental fruit moth? I was impressed by the posted results from bread bags, which have microperforations, but of course zip locks are much easier to work with.
Did you still cut out the bottom corners for drainage as one does for apples?
And how did you keep the bags together while drilling?
Sorry if you’ve already covered this elsewhere, if so maybe just post a link.
I have had no need to bag cherries( yet). If I were I would not used plastic ziplock the way I do with apples. I think it won’t have enough ventilation.
Bread bags would be my choice. I don’t know how expensive bread bags where you are. Here they are pricier than zip lock but reasonable.
Hi Mamuang, you are right. I can buy bread bags cheaply but it takes time and multiple losses to fix them around the fruit with wire or ties and all the bunched up material. I am looking for a well-ventilated solution with the convenience of zip lock bags - they are just so much easier to secure around a stem. Hence the exploration of ways to create ventilation in a zip lock bag.
Right now the plan is to secure a stack of zip locks using foldback clips, then try either running it through a sewing machine or using a fine drillbit.
Auburn, did you find any difference in results between the drilled bags that had the corners subsequently clipped and the ones that didn’t?
The drilled bags with several holes stayed dryer. Most all the bagged fruit was i n good condition when picked
This year I’ve used all kind of bags. For clusters of fruit, bread bags are the best.
Your fruit looks well protected with the bread bags. I zoomed in for a close look and I was impressed with not seeing any moisture. I think they will mature well and I hope you will do some followup pictures at ripening time. Bill
