Terrence’s leafless ficus plant. Source: Terrance Keller
Question: I accidentally left my ficus plant outside too long and all the leaves died. I cut it back very drastically and am now wondering if I’ve killed it. It’s sitting in front of a south-facing patio window so it will get as much sunlight as possible in the winter. Is there any hope?
Answer: Yes, it’s possible that it will resprout, but it depends on how much cold it suffered and how long the cold lasted.
Houseplants are very variable in how much cold they can take. There are various species of small-leaved indoor figs, among which Ficus benjamina is probably the hardiest, tolerating a touch of frost for short periods, especially when it’s mature, while F. microphylla isn’t as hardy and can be severely damaged or even killed at 55 °F (13 °C) if the cold is prolonged.
The only thing to do now is to wait and see. Give your plant normal indoor temperatures and barely any water, only enough to keep it from drying out totally. You don’t want to overwater at this point, as the roots will probably have been damaged as well, and sitting in damp, stagnant soil can lead to root rot.
It may take two months or more before your plant reacts, especially at this time of year (plants recuperate more slowly when days are short).
If nothing happens … well, at least you tried!
If new growth does appear, make sure the plant continues to get good light and begin to water as needed (when the soil is dry to the touch). Increase air humidity if possible during the winter months. Don’t fertilize until the plant is growing vigorously. Then, as it begins to fill in, you’ll have the task of selectively pruning to get rid of the dead wood and leave space for the new growth.
No need to feel guilty about this. I think most gardeners occasionally forget a plant outdoors in the fall. I clearly remember bringing in a potted windmill palm (Trachycarpus fortunei) I had lost track of in my garden (I knew I hadn’t brought it in, but couldn’t for the life of me remember where I’d put it!) and only found it when the weight of the snow pushed down the surrounding vegetation, revealing it standing upright with snow all over hits leaves. And yes, although it lost most of its fronds, it did survive!