Freezing weather and watering!

We’re having a week of overnight freezes here in Portland, Oregon following a few days of bright sun and drying winds. The pots are—for once—drying out.

One of the most dangerous things about freezing weather for bonsai is dry soil. Pots breaking is truly a secondary concern. Bad root damage can occur if there is not water in the pot to insulate the roots when it freezes. Otherwise you get a double whammy—freeze dried roots.

So get out your hoses…or spot water with a can…and protect those roots. If you have frequent freezing in winter storage, then watering should be more frequent than you might think. Freezing has one other side effect…it dries out the soil.

In Japan, Mr. Suzuki would have us try to thaw out the bonsai each winter day a bit, so that we could water them. This is a bit contrary to what we hear in the west. But it makes sense.

Stay warm…


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  1. Tim Gardner says:

    Hi Micheal. That makes sense to me. I hear quit often the contrary. Once the trees have frozen you don’t want them to thaw, because the expansion and contraction will tear roots.

    Truthfully, that never made any sense to me. How would you stop them from thawing when the low is thirty and the high for the day is fifty two? It never made sense to me for that reason alone. I guess if you live in the North it would be that way, provided that you don’t have a greenhouse.

    I also hear your trees do not need light in winter, I am not sure that I agree with this as well. Trees in nature get light all winter long. I would love to know your thoughts on that.


    • crataegus says:

      About the trees not needing light—I’ve heard a few reports from sources I respect to the contrary, but in my experience they do not need light. At least, and I should qualify that, when I had bonsai in Upstate NY where the winters could reach -20 F and the trees if kept in a cold frame would get completely, utterly dormant. I had deciduous and evergreens that did just fine in a hole dug in the ground and a piece of plywood thrown on top. This was pretty rustic I admit, but it worked. They budded out fine in the spring. There is a possibility that trees sort of half-dormant—like those in my area, as we see root growth throughout the winter—need some light.

  2. Mark says:

    Not ALL trees in nature get light all winter long. Trees in the mountains can be buried in snow with no light for months and months. I had an Engleman (sp) Spruce which was covered totally 6 months of every year, until it left home to live with me.


  3. Tim Gardner says:

    Good point Mark.


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