hydrangea tree potted, winter inside

Question

I brought my tree inside. The leaves have dropped and the flowers are drying. Do I water it? Do I cut it back? How do I control the top soil mold?

Answer 1

When you bring a plant indoors, the light (from the plant’s viewpoint) suddenly becomes much less. A plant’s response to this is to drop a bunch of leaves, and flowers if there are any, in order to balance the energy production (leaves produce energy) with the energy spent (maintaining leaves and flower requires energy.) In other words, if you can’t make as much energy, you have to stop spending so much. This is what your hydrangea is doing. From our point of view, what we can do is make it as easy for the plant to transition from outdoors to indoors by acclimating the plant. Read more here: https://www.gardeningknowhow.com/houseplants/hpgen/acclimate-plants-indoors-winter.htm
Some plants can be moved indoors and kept as houseplants, with foliage and sometimes flowers. Some plants need to be cut back and overwintered in a state of dormancy in a cool, darkish cellar or garage. Hydrangea is one of these. This article has more information: https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/hydrangea-winter-care-how-to-protect-hydrangeas-from-winter-cold-and-wind.htm
You are going to want to cut back your hydrangea, and water very lightly, just to keep the soil from getting completely dried out. If you have mold on the top of the soil, scraping off the surface of the soil should be enough; as the soil dries, the mold will die. Mold indicates the potting medium is too damp.