Geraniums (Pelargonium) are among themost popular flowers for window boxesin general and delight the eye with their beautiful flowers until autumn. Contrary to popular belief, geraniums are actually perennial and can survive the cold season through proper overwintering. In this article we explain how you can overwinter geraniums so that they survive the frost and get through the winter safely.
When do geraniums overwinter?
After the first frost, many geraniums are discarded and replacednew plants in springreplaced. However, these balcony flowers can survive the winter if you overwinter them properly. When is the best time for wintering depends on various factors.
What temperatures can geraniums tolerate?
Geraniums can tolerate temperatures of up to 5 degrees below zero for a short time, especially if they are kept somewhat protected on the balcony. The plants can tolerate light frost, but they should be frosted before the first real frostto winter quarters. In our latitudes, this usually happens at the end of October, but depending on the weather, you can also overwinter your geraniums in November.
What to do if geraniums get frost
If your geraniums have suffered frost before you can move them indoors, there is still a good chance that you can save the plants. So if only the leaves are frozen, just cut them back. Geraniums whose stems have not frozen despite the frost will sprout again next year without any problems.
Overwintering geraniums: an overview of the different methods
Although geraniums are not hardy, you can easily get them through the winter with a few simple methods. Geraniums can even be overwintered in a flower box if there is enough space in the winter quarters. Another option would be to take the plants out of the box, cut them back and overwinter them in boxes. Alternatively, geraniums can be hibernated hanging with the root balls wrapped up. We'll show you exactly how each method works below.
Pelargoniums overwinter in pots or flower boxes
Geraniums that grow alone in pots or flower boxes can also be overwintered there. The winter quarters should ideally be dark and cool, otherwise the plants will sprout early. A temperature of 5 to 10 degrees Celsius is optimal. During wintering, geraniums are really easy to care for - just water them from time to time and check for rot. Fertilization is not necessary.
Important: Areother flowers in the flower boxplanted next to geraniums, then this method does not work well.
Overwintering in newspaper: Unpot the plants and cut them back
In order to save geraniums over the winter in a space-saving manner, you should take them out of the flower box and bring them into their winter quarters. There are also different variants for this.
First, pot up each plant with a hand shovel and gently shake off the soil from the roots. You can place the plants in a shady place and let them dry for a few days. This will prevent the formation of mold or mildew.
Before you bring the pelargoniums into their winter quarters, the plants need to be pruned. To do this, cut the shoots back to around 10 centimeters and remove the majority of the leaves to avoid pest infestation. The plants will sprout from the thickened nodes that remain next year.
Then wrap each plant in newspaper and place the geraniums side by side in a box for the winter. No special care is required during the period, you should only occasionally spray the shoots with water so that they do not dry out.
Geraniums can be hibernated hanging over the winter
With this variant, you overwinter the pelargoniums hanging in plastic bags. To do this, first cut the plant back in the flower box to around 10 to 15 centimeters. Then remove the fallen leaves from the flower box.
Prick out the root ball with a hand shovel and cut off all leaves. Pack the root ball in a freezer bag and seal the top of the bag around the shoots with some string or binding wire. Then tie a piece of string to the bottom and tie a knot. Hang the geranium bags upside down (with the shoots facing down) in a cool, unheated room such as the garden shed.
Here are some tips to help plants survive the winter:
- Store the geraniums in a cool, dry place, around 5-10 degrees Celsius (never below zero).
- About once a month, check whether the shoots are moldy and remove any dried parts.
- Also check the stems - they should be firm. If you find any shriveled, dried stems, discard them.
Traditionally, geraniums are stored upside down, which forces moisture down into the stems.
Overwintering hanging geraniums: This is how it works!
Although hanging geraniums are not winter hardy, the heat-loving plants can also be overwintered. After pruning, they don't need any brightness and can therefore survive the cold season. You can use the same method as with standing geraniums. Here we have summarized the steps for overwintering hanging geraniums:
- Remove all shoot tips, buds, flowers and leaves.
- Cut back stems and remove dried areas.
- Remove the plants from the flower box and shake off excess soil.
- Pack root balls in transparent plastic bags and hang the plants upside down in a dark, cool place.
