Overwintering geraniums is easy, if you follow these simple steps

Overwintering geraniums – aka pelargonsjuka – has well and truly cemented a place for itself on our list of must-try garden ideas.

It's an age-old concept for many gardeners, of course, but the art of coddling our geraniums became a seriously hot garden trend earlier this year when it was dubbed one of several Scandi garden design ideas worth stealing.

So, how do we go about this then?

Overwintering geraniums: a how-to guide

'Also known by their horticultural name of pelargonium, geraniums are one of our most popular summer plants,' says Morris Hankinson, director of Hopes Grove Nurseries. 

Morris Hankinson

Morris Hankinson is the founder and managing director of Hopes Grove Nurseries Ltd, the UK’s only specialist grower-retailer of hedging plants, which he established after graduating with a Commercial Horticulture Degree from Writtle College, Essex in 1992.

Noting that they hail from warmer, drier climates, Morris explains that the key to overwintering geraniums is to keep them dry and frost free.

However, there are several different methods of overwintering available to you, which are as follows:

1. Bring them indoors as houseplants

Perhaps the most famous form of overwintering geraniums, you'll be pleased to hear that you can 'keep the same plants from one year to the next by bringing them inside about six weeks before the first frost,' says Morris.

If your geraniums are already in pots, you can keep them as is: let the pots go fairly dry (but without drying out completely) and bring them indoors for overwintering. 

If your geraniums are planted in your garden borders, however, Chris Bonnett, founder of GardeningExpress.co.uk, says you can absolutely dig them out and pot them up with fresh soil.

'You’ll want to prune the plants by half to encourage growth next spring,' he adds. 

Either way, overwintering geraniums as houseplants means finding them a spot on a sunny windowsill (ideally around 12°-18°C), watering them only when the soil becomes dry to touch. 

2. Take cuttings

Fun fact: learning how to take geranium cuttings is absolutely a form of overwintering geraniums. Who knew, eh?

3. Bare root storage

Only suitable for overwintering geraniums with thick, woody stems, this method demands that you:

• lift plants from the ground before the first frosts
• shake excess soil/compost away from the roots
• dry them off
• wrap them in newspaper or paper bags and hang them upside down from the ceiling (alternative: place them in cardboard boxes)
• check on them every few weeks and moisten them
• inspect them in the early spring for new growth; discard those without any
• soak them in water for a few hours
• pot them up and cut back all stems to about 10cm 
• water sparingly and keep them in a greenhouse until they're ready to be hardened off and planted outdoors

4. Cool storage

Another riskier method of overwintering geraniums, this one asks that you cut the plant back by one-third to one-half, wrap their pots in bubble-wrap, water deeply, and stash them in an unheated greenhouse or shed.

Some people prefer to cover their plant babies with a garden fleece like this one from Amazon, just as an extra precaution. 

Whether you do or not, keep checking them for signs of disease, keep the temperature at around 2 to 4°C, and water sparingly when they show signs of drying out.

Personally, we're fondest of the first method for overwintering geraniums, as it means we get to enjoy them and coddle them for longer. How about you?