Care for winterizing summer plants

Asked January 30, 2019, 10:26 PM EST

I have many of my summer plants indoors and so far, besides looking a little straggley, they are living. Some in our hot tub room, others in front of sunny windows. Geraniums, begonia. Fern, 2 hibiscus trees, and another tropical. Can I cut them back now? Can I transplant them into bigger pots? Any fertilizer recommendations? Geraniums did great last winter but I didn’t do anything except water a little bit. Took a long time to bloom once outside in spring. Thank you Kathy Mathews

Washington County Minnesota overwintering geraniums overwintering propagating begonias

1 Response

Thank you for the question. Many summer plants can survive our winter when brought inside, but they don't often thrive. In fact, they just get by, waiting to get back outdoors once the temperatures warm up.
Some plants such as the geraniums and begonias will produce flowers sooner next season if you start new plants from the old one. You can still do this. There are instructions on how to do this in our publication on growing geraniums:
https://extension.umn.edu/flowers/growing-geraniums-annual-flowers-minnesota Scroll down to the section labeled "Growing Geraniums Indoors" and then, "Propagating new plants". The information applies to begonias too.
If you choose not to start new plants, you can cut back the old ones part way and transplant if needed, into a slightly bigger pot. Plants grown indoors for the winter don't often need fertilizer, only if they are actively growing. This usually starts in the spring when we get more sun and the temperatures warm up. The same publication reviews fertilizer usage.
The hibiscus trees can be lightly pruned for shape. Flowers are produced on new growth so you will sacrifice some blooms with the pruning. Follow the same fertilizer recommendations for all the plants.
I'm not aware of techniques for pruning ferns. If the fern you have is large, you may want to just pinch off new growth for awhile to maintain it at its current size and then let it go once it's back outdoors.

Thank you for contacting Extension.