Contrary to popular belief and ideas, Gunnera (not part of the rhubarb family!)is not susceptible to die during winter as long as it receives proper care. Gunnera is native to the warm climates of Chile but because of its cold-hardy characteristics, it has become well adapted to much colder climate regions like the UK. Keeping in mind that Gunnera is an invasive perennial, it will die after every season before new growth emerges in a new growing season and not necessarily because of winter.
However, regardless of the cold-hardy nature of gunnera, it can sustain some serious damage during extremely cold and dry winters especially if it is not properly protected from the frost. If you are interested in buying gunnera, have a look at a list of UK suppliers of Gunnera here.
Gunnera is easy to grow in the UK, read this Gunnera grow guide for more information.
How do you overwinter gunnera?
How To Overwinter Gunnera in the UK
Overwintering Gunnera is not a complicated process whether it is in the ground or if you have the gunnera in a pot. It is a process of insulating the stem crown and protecting the root system. This can be done in a couple of minutes using the right tools. You need a pruning saw or a knife to complete the 4 steps of overwintering Gunnera. Here are the 4 simple steps:
- CUT and FOLD: Using any of the tools mentioned above, cut off, or fold over the leaves of the gunnera plant just at the top of the stem.
- FLOWER STALKS: Next, cut off the remaining stems and leave them all short stubs. Also, cut off the flower stalks and set them aside. Most gardeners prefer using a knife for this step to avoid getting injured by the prickly stems of gunnera.
- COVER: After the first two steps, what you will have is the exposed fleshy crown of the gunnera plant. Simply cover the crown with a layer of the freshly cut leaves pushing them on the protruding stem stubs to keep them in place. Add more layers of leaves to the fleshy crown on all sides.
- DISPOSE: Lastly, take the freshly cut stems and dispose of the flower stalks.
When do you overwinter Gunnera?
Usually, the best time to start preparing your Gunnera for the winter is after the frost begins to appear and you notice minor foliage damage on your plants, usually mid to late October.
Starting the overwintering process too early will make the insulation and rotting process of the leaves happen much faster and too early which can lead to premature exposure of your plant to the cold weather as well as permanent damage to your Gunnera plant.
Is gunnera frost hardy?
Gunnera is generally frost hardy but below certain temperatures, it can obtain significant damage if not adequately protected.
Read more:
- Gunnera grow guide
- Best places to find gunnera for sale in the UK
- 5 Tropical winter hardy everygreen plants for UK gardens
