Last year, I bought a young Japanese maple from a greenhouse. I hoped to turn it into a Bonsai. I was told that it wouldn't survive the winter outdoors, but that many people keep them indoors as houseplants. I brought the maple inside in the fall. Within a couple of weeks, it lost all of its leaves. They didn't change color - just dried up and dropped. I kept them in my sunroom with an East-facing window. Its cooler than the rest of the house, with night temps about 12 degrees Celcius and daytime temps 15-18 degrees Celcius in the winter. In March, the JM started to get buds. Unfortunately, these buds did not progress. The tree does have lots of new growth arising from the lower 1/3 of the trunk. The buds have dried up. I thought the top of the tree had died back, but I scratched the bark and found that it was still green. Any idea what happened? Should I prune it back to where the new growth is, or will I eventually get new leaves on the branches? The new leaves that have erupted at the bottom seem to be flourishing, and the tree is now outside for the summer again.