Little Tree, Don't Die On Me

December 2, 2015 8:29 PM

Dear gardeners of MeFi: I have a small Japanese Maple in a container. It's susceptible to frost, but the weather's so weird (thanks, global warming) that I'm not sure whether I'm killing it with the wrong sort of care.

The fellow at the garden center where I bought the tree said to move it inside the garage and wrap it in burlap when nighttime temperatures got below freezing. They dipped that low a few weeks ago, so I moved the little tree inside, etc. But now things are going to start warming up again during the day, to the point that it'll be 60 degrees out in the afternoon. Am I killing this tree? How should I best take care of it in weather like this? It's not getting any sun in the garage.

Obviously I don't have a very green thumb.

posted by Miss T.Horn to Home & Garden (3 answers total)

Best answer: I would keep it in the garage, wrapped in burlap. Dealing with unseasonable weather is hard and somewhat out of your control, but you want to do as much as you can to encourage the tree to stay dormant until spring. A dormant deciduous tree doesn't need much sun, because it isn't very active. If you put it out in the nice warm sun, it might get confused and start to wake up, which means that the sap would start to flow more and it might start putting energy into building new leaves (which will get burnt or killed the next time it gets below freezing). Putting energy into building new leaves that don't survive weakens the tree, and that can ultimately kill the tree if it happens too many times. You're doing the right thing by keeping it in the garage.

If it helps, you can think of it this way: deciduous trees need to sleep all winter the way people need to sleep 8 hours a night. If a tree "wakes up" several times in the winter when it should be sleeping, then it won't have as much energy in the spring (which is when it needs the most energy, so it can put out a whole lot of leaves) just like a person is pretty groggy and tired if they get woken up multiple times during the night.
posted by colfax at 2:53 AM on December 3, 2015

Best answer: Putting energy into building new leaves that don't survive weakens the tree, and that can ultimately kill the tree if it happens too many times.

Twice is all it takes. Couple years ago it frosted hard after the first leaf buds were out, killing them. A couple weeks later, after the second set of leaves emerged it frosted hard again, and killed the second set. Apparently two tries is all you get per season; young and old trees alike died that year.

We move our potted Japanese maples into the garage after all leaves are dropped and temps dip to freezing. They stay there all winter until most chance of frost is passed. This usually means that they have started little bids. Resist the urge to move them out on 'nice days', and give them just a little bit of water to keep them from drying out. Don't worry about how much sun they are getting. Temps in my garage do go below freezing, but not much and not for days on end. I actually think the moderation of temperature swings that the thermal mass of the garage gives helps maintain the dormancy.
posted by achrise at 7:46 AM on December 3, 2015

Think about it this way: the tree doesn't know that there's an unseasonably warm spell going on out there. For all it knows, it is frosty and cold. Let it stay dormant in your garage, dreaming of spring.
posted by sciencegeek at 3:20 AM on December 5, 2015