Bag treatment

On the page which I visit the most to find more information (from a friend and a member of our local bonsai club, really a good page) I have found already earlier the way how to arrange longer trips without having anyone water the plants.

The idea is to water the tress, let them leak out any extra water thoroughly and then close them into transparent nylon bags to keep the humidity from escaping from the tree.

I did the same before I left for the trip to Thailand.

The first 2 photos are of Japanese maple which is not yet a bonsai tree. It is just a tree I keep outside in the front yard and perhaps sometimes later I will make it a bonsai. It was in the outside unheated storage with a thermometer and in a separate bigger pot filled with wrinkled paper sheets for insulation. This winter had several very very cold days (-27C) and when I panicked I took the tree in January inside directly into the same transparent bag as the other ones. It did wake up and started producing leaves so it did survive several days in about -15C which in my opinion is quite a feat for that specie 🙂 Later I will update on this tree, when it goes outside.

The rest of the trees are in separate nylon bags and on my sons working table near the window. February in Finland is not so sunny to be afraid of cooking the trees (actually there was no sun all 2 weeks) so they can all remain where they are for the trip length.

When I closed the tree inside the bag I also wrapped a thread around the bag right above the pot upper edge. The idea was that when the water condenses on the bags walls they would leak down and I wanted them to end inside the pot, not gathered in the bottom of the bag where the tree will not be able to take it from.

After the trip I checked the trees. Several notices:

  • All trees survived, at least none of them yet died and definitely not due to the bag treatment.
  • Every dead leaf in the pot or hanging on the branch got fungus. This needs to be remembered next time when I close them, first cleaning!
  • Though the trees look quite “wet” the pots are actually quite dry (as noticed on the janinbonsait page linked above). The tree sucks the water from the pot and evaporates it into the nylon bag. All is fine as long as the bag is still closed. I had to water a day or 2 after I opened them, they all got completely dry.
  • Some of the leaves (ficus for an example) fell of the tree, I assume due to dryness in the pot or perhaps just because of non-standard growing conditions. Though the trees were near the window the light is insufficient for any tree to grow… survive maybe.
Otherwise I am very satisfied with the end results 🙂 Will repeat it again when needed.

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  1. Jani

    Good tip that thread around the bag! Will definitely test that.

    • tato

      Thanks for comment.
      Though the bags were not wet on the bottom (hopefully due to the thread I tied around) I didn’t have a “control group” of several trees without the thread to confirm it works well. Majority of trees were awaken from the heated winter storage so they didn’t really “steam” so much inside the bags yet, another probable reason for bags being not wet on the bottom. Good if you also test it, we then see if it is of any sense to continue using it.

  2. B-Snaga

    Interesting. But how the tree gets enough CO2 if the bag is closed?

    • tato

      Thanks for comment!

      They don’t 🙂

      The bags are there to keep trees survive without daily care for a defined period of time rather than development and growth. Most of the trees were just awakened from winter “sleep” and all of them were located, due to dark winter, into not so light place which makes them not need to much of CO2.

      I have read somewhere that bags (some or all, don’t know) let allow CO2 exchange but not let humidity escape. I don’t have a reference anymore so I can’t confirm acuracy of the statement.

      • B-Snaga

        Hmm, perhaps the similar can be done with other plants and flowers, isn’t it so… and I wonder if the plants are closed, don’t they then have too much humidity on leaves over too long period of time. Or maybe it does not matter?

        • tato

          Yes, correct observation. The same can be done for all plants but none of them should be for too long period inside. The plants actually survive on only the air humidity, all water is sucked from soil and remained dry so plants which cant handle that shouldnt be pushed into that stress.
          If too long mold start gathering but that also depends if there are dead leaves because there it starts. If the plant is clean and only living tissue exists then it goes fine.
          I would say max 2 weeks I would be ready to keep them in.

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