Geraniums — at least what we commonly call geraniums — are the workhorses of the summer garden. In full sun, they bloom all season.
We often find a special one that we wish we could over-winter. Pellegoniums originated in South Africa, where they actually grow as small shrubs. Sadly, the first nights of 40 degrees will kill our summer lovelies.
Here are your choices:
You can kiss the plants goodbye. Let them die back and compost them.
The advantage of this option is new is better and who knows what is waiting at the garden center next spring. Starting with new plants ensures that they will take off in your landscape and will be ready to make any sunny spot colorful.
You can bring them into the house and attempt to make them into houseplants.
This is the most problematic option. The plants will need to be transplanted into huge pots, which are bulky and heavy. Most outside plants resent being brought inside, and they will pout. The plants will lose their leaves; they will quit blooming, and the leaves will get smaller and smaller because you cannot provide as much light as the geraniums were used to outside.
Even worse, the plants become a magnet for bug infestations. You name it, geraniums attract it: aphids, spider-mites, scale, white fly. And these infestations will travel to your other houseplants. Who knows, the plant’s soil may be harboring some exotic pest such as spiders or earwigs or slug eggs.
You can bring them into a sheltered space and over-winter them.
Geraniums have been in our gardens since the 1720s, and they can be surprisingly long lived. My geriatric geranium is now 32 years old. It goes outside in a pot in the summer, and winters over inside.
There are as many over-wintering techniques as there are grandmothers who did this for years. Some of the techniques are more trouble free and more successful than others.
Barerooting: You take the plant out of the pot and leave on as much soil as possible. Some people hang the plants upside down in the garage. I found no actual reasons for why the plant has to be upside down. Some people put them in brown paper bags. Essentially, the plant is forced into a droughted dormancy. You can check on it every once in a while. It needs no light but needs a sprinkle of water every once in a while. It does need to be stored in a place that is about 45 degrees.
This technique is not as successful in North Central Washington as it is in other parts of the country that have higher winter humidity. We are both dry and cold during the winter. Try this technique with plants you have not fallen in love with.
Resting: Cut the plant back by 75 percent and put it in a 45 degree room with some light. Water only if the plant is really dry. This plant will put out some new growth — be sure to check for insect pests because they can easily kill the plant in a short amount of time.
Watersprouts: In the fall, take cuttings about 12 inches long and remove most of the leaves and all the flower buds. Put the stems in an opaque container filled with water. Check the water level every once in a while and be sure none of the leaves are rotting in the water. The stems will root. When they have rooted in late February, move the stems into moist potting soil. Put the plant in moderate light so that it can sustain itself until you are ready to plant it out-of-doors.
A final warning
After you have spent the winter worrying and mussing about the plants, the plants must be hardened off before they are planted outside. Beginning in mid-April, move the plants daily outside for longer and longer periods and into more and more intensive light. And they must be brought in every night.
Generally, the plants are not ready to transplant out into the garden until Mother’s Day because the soil is not yet warm enough. You can tell it is not warm enough because the leaves develop red leaf margins.
Option 1 is a great choice for some. I personally do Option 3 both as water sprouts and resting, heavily pruned plants.
A WSU Master Gardeners of Chelan County column appears weekly in the At Home section. Bonnie Orr is one of three columnists featured.