Winter is comming for my Elm, what is normal and what is not?


(Johan Jansson) #1

Hey bonsai tonight!

My name is Johan and i live in the middle of Sweden and we have about 10 to 25 CELCIUS + in summer and 5 to 18 - CELCIUS in winter (it can get really cold sometimes…)

About 6 months ago (midsummer) i bought a healthy and perfect bonsai tree (Chinese Elm) from the UK. My tree is about 9 years old.

It has been growing inside my house in the kitchen ever since then with 100% placement at the window. I have never taken it outside, only opened window sometimes for air draught…

I understood early that the tree is forgiving, cause i gave it to little water and leafs turned browned and the tree became naked quickly… I started to water it and it bloomed back quickly with healthy green leafs and also starting to make new shoots!

Now we are going in to December and my tree has slowly dropped alot of leafs… They have gone from bright green to yellow tones slowly, then falled of. The leafs this time has never become brownish like when i overwatered it.

Only the newest shoots are still flexible with green and healthy leafs right now (which came later in summer) The tree has about 25% leafmass left ALMOST only from the newer shoots / small branches.

Questions:

  1. Is my tree trying to find some kind of Dormancy cause the lack of sun hours? ( Is this leaf dropping normal ?)

  2. How much water should i give it given the information i now have? ( Wait until soil turns almost dry before wateringsessions? )

  3. IF the tree is struggling to survive, what am i doing wrong?

  4. If the tree needs a new place to rest, is it risky to move it to colder/air-like place cause its not used to - CELCIUS ?

  5. Is there anyway to see what kinda of region my tree been living if for all these years, was these Elms imported from northern/southern china? (Can it take a cold swedish winter?)


(Sely) #2

Hello, Johan_Jansson!
I live in a slightly warmer climate and from my understanding on Chinese elms is they are hardy to zone 5 (-28.8 C) in the USA and I’m at zone 8 (-12.2 C). Which means your between zone 6 to 7.
I personally think that during the winter months that the tree does not need quite as much water and nutrients due to insufficient lighting and air circulation. Just allow the tree to dry out a little more than normal.
I had never tried growing them indoors but had some friends that do. Mine are typically outside and are mostly Chinese elms of various varieties- corkbark, catlin, seju, and yatsabusa, which are all doing great.
Dormancy allows an opportunity for your tree to rest and gain vigor for on coming seasons.
If your not quite sure, then make a few more plants from root cuttings and test it out next year. And remember to rotate your tree 90 degrees every few weeks to give it light all around or it will get weaker on the side without light.


(Jonas Dupuich) #3

Hi Johan - @Sely’s points are good. As for your specific questions:

  1. yes, now’s the natural time for the tree to enter dormancy
  2. as you and @Sely say - water when the tree dries out a bit
  3. it’s a lot harder to keep elms happy indoors than it is outdoors
  4. yes, it can be risky - see suggested reading from @crataegus001 (Michael Hagedorn) below
  5. the tree may have developed anywhere - the main question now is whether or not it is winter hardy; I wouldn’t expose the tree to prolonged hard freezes below -2C

Two great articles about winter hardiness:

And a recent article on elms:


(Susan) #4

Apart from the time you forgot to water our Elm your tree has been healthy. Once you watered again new growth returned so this shows your care for the tree inside is working for you. Your Chinese Elm is a deciduous tree at this time of year leaves will yellow and fall. All this is normal due to less day light ours and tree resting over winter. The only thing that you must be very cautious of is the tree being inside in winter with heating. Indoor heating will dry your tree faster so you must watch your watering best idea would be to soak your tree at least once a week or even twice depending on how hot you have our heating. Ensure you allow water to drain away and not sit wet in a tray. It is correct that trees without leaves do not require more water however that is for trees outside that get overnight frost, dew, and natural rain fall etc… As your tree has been inside I would not put it outside as it is not conditioned to cope with this sudden change. Keep doing what you have been doing, only now watch that your tree does not dry out. Once you see buds start to form in Spring start to fertilize your tree to encourage new healthy growth.
Cheers