According to the University of California, outdoor geraniums should be kept frequently watered, especially if they are in pots, to help protect them from an unusual cold snap. In comparison to dry ground, which will instead rob moisture from the roots, weakening the plant, moist soil that freezes causes less damage to plant roots.
To shield geraniums from the cold before light frosts, cover them with “tents fashioned from newspaper, cardboard, a bed sheet, or burlap. Avoid letting the cover touch the plant itself because this will allow the geranium to become frosted. Place mobile geranium containers in safe settings, like next to house walls, which are typically several degrees warmer.
What degree of heat should geraniums be covered with?
Geraniums often won’t withstand a strong freeze, with the exception of a few of the more uncommon species. Temperatures below 25 F will also damage stem tissue. If you plan to use yours as winter houseplants, move or cover them if it is predicted that the temperature will drop below 29 F to prevent harm.
Do geraniums recover from a frost?
The geranium will keep any uninjured leaves and stems if the weather improves after a frost or freeze in the garden. Depending on the weather, it may start to develop again from the tip of the stem or go dormant until the right amount of warmth returns in the spring. Frost-killed leaves and stems turn black and dry, however there may be some rotting of soft stem tissue where dead tissue meets living, moist tissue.
- Geranium plants cannot be subjected to frosts in order to be permanently evergreen, remaining alive with all of their leaves and stems.
- When air temperatures dip and stay between 25 and 28 degrees Fahrenheit, plants can suffer significant damage or even die. The geranium will keep any uninjured leaves and stems if the weather improves after a frost or freeze in the garden.
degrees and filtered sun WHOOPEE! watch me grow
The majority of the time, geranium family members thrive in this setting and spread like weeds. Naturally, certain kinds prefer different environments and can withstand extremely high and low temperatures. Some Hardy Geraniums, for instance, may endure temperatures as high as 100 to 110 degrees while also withstanding full sun in the central valleys and temperatures as low as 20 degrees.
As a general rule, 50% shade cloth fastened overhead can give the right amount of sun exposure, with temperature acting as the only threat. Air conditioners and greenhouses were created for this reason. The golden rule is to never place a geranium in an environment in which you wouldn’t feel at ease. Many books, nurseries, and magazine articles may advise readers to “Grow in full sun,” yet these texts were all written from mild climes and do not applicable to California’s Central Valleys and foothills.
Geraniums are just like people
They dislike both excessive heat and sunlight, and they dislike sitting outside on a cold morning. Just like us, they all have varying tolerances for high and low temperatures.
Grow your plants in pots so that you can move them to different locations with better microclimates.
I’ll move my plants about until I see that each type has settled into a nice area. It might be challenging to choose the ideal location in your yard or greenhouse because each type has a different tolerance to heat and light.
Don’t forget to cover your plants with frost protection. When I know there will be a hard frost, I bring my inside and let them watch The Garden Channel on TV; they enjoy that.
Variegated & Yellow/Green Leaves
Plants with variegated leaves or leaves that are yellow or green do not tolerate the sun and heat as well as kinds with “green” leaves, and they thrive in cold coastal areas or air-conditioned greenhouses.
These plants can thrive from October to mid-May during the chilly season in the central valleys. During the warm season, the plant will “stress,” showing dry edges to the leaves and slowing its growth.
Reduce the amount of fertilizer and offer daytime shade. It is ideal to keep the plants in containers on the ground, where the air is the coldest.
How can cold temperatures be avoided when growing geraniums?
Geraniums are incredibly simple to store for the winter—just place them in a cardboard box or a paper bag and secure the top. The following advice will help them survive:
- Maintain geraniums in a cool, dry area with a temperature of 50 to 60 degrees F.
- Once a month or so, remove dried leaves from the bag or box and check for mold.
- Check the stems quickly at the same time; they should be stiff. Throw away any dried-out, shriveled stems you uncover.
- If you see that the plants are becoming really dry and crispy, give them a brief soak in water.
- Plants with stems that appear to be blackened or mildewed should be disposed away.
Geraniums are typically kept in a sack upside down. Although the exact cause is unknown, one idea holds that it does so by pushing moisture into the stems. Whatever the cause, storing them in this manner is neither harmful nor necessarily harmful.
Can geraniums withstand a little frost?
According to the University of Florida, one of my favorite container plants, geraniums, cannot withstand a cold. However, if they have had some time to acclimate to the chilly weather, they may endure a light frost.
I’m not sure if it switched from frost to freezing because I was away during that brutal cold snap in mid-December. It appears to have been below freezing, at least out here in the hinterlands west of State Road 7, based on what I heard about the temperatures.
But when I got home, my potted geraniums were the only thing in my yard that looked truly decent. The majority of them were covered in large, colorful flowers despite not being moved, covered, or even watered.
Another surprise was that the orchids, predominantly dendrobiums, that I have attached to trees received no particular care. When the weather went northerly, many spikes had buds, but now they are all in flower. Even though some of the flowers are not as spectacular as usual, they still seem good.
I suppose I’ll pay attention when I do my research in the future before planting a bunch of one kind of shrub and notice the warning “extremely cold sensitive.” When I positioned a dozen vibrant copper leaf shrubs across my back fence this past spring, I simply glossed over it. They went brown and crunchy after the first cold snap and quickly lost all of their leaves. I don’t really want a whole line of plants that will make me think of my Chicago yard in the winter every time the temperatures drop and then take the rest of the season to recover. However, after about a month there were a few tiny signs of life. They’ve left.
I intend to replace them with coco plum, a gorgeous native bush that creates a nice hedge, once I am confident that the worst of the bad weather is behind us. The coco plum has been described as “sensitive” in certain writings, but the majority of the study I did shows that once they are established, they are hardy. They appear to hold up reasonably well based on what I have seen so far this year. Definitely superior to both my copper leaf and my ficus, which was badly damaged.
How can I describe my ficus? They’re supposed to be recovering from the white fly infestations of the summer during this time of year, right? Sadly, it turns out that these plants, which were formerly thought to be indestructible, are also cold sensitive. They don’t seem to have ever looked this horrible to me. The weeds that snake through them and span the tops, which at least had the advantage of keeping them looking green most of the time, turned black from the cold, adding insult to injury. The 200 feet of ficus along the side of my property line was undoubtedly the worst gardening decision I made during my first year in South Florida.
Given that South Florida does not frequently experience this kind of weather, you might not anticipate native flora to handle it very well. But my geraniums are the only item that look better than mine because they have been such soldiers.
Are geraniums susceptible to frost?
Knowing how to overwinter geraniums is very useful for gardeners since it can help them save money and extend the life of particular varieties they enjoy.
Pelargoniums, sometimes known as geraniums, are mainstays of the summer garden. Geraniums are ideal for adding cheer and long-lasting color to hanging baskets, containers, and borders since they come in a variety of colors and flower continually as long as they are deadheaded.
However, when making your job list, you might consider including them as one of your winter garden ideas.
When growing frost-sensitive plants, planning a winter garden is crucial. Geraniums are perennial plants that put on a long display, but they are frost tender, which means they won’t survive harsh winters. If you are interested in cultivating geraniums, you must learn how to overwinter them.
Geraniums are South African natives that thrive in the heat and can withstand periods of drought with little water.
Pelargoniums, sometimes known as geraniums, may live in USDA zones 7 to temperatures of -12oF (0oC) if they are sheltered. They are hardy in climates between 20oF and 50oF in zones 9 through 12. They need to be sheltered in these conditions because, while they can withstand brief frosts (temperatures slightly below freezing), they cannot withstand prolonged exposure.
The Pelargonium genus contains a wide range of cultivars, all of which are categorized as delicate perennials. According to David Taylor, vice chairman of the UK Pelargonium and Geranium Society, “this means that they are not cold hardy as the majority of the founding species come from the warmer climbs of the Southern Hemisphere.
Perennial plants are able to flourish for a number of years, however in the UK this would mean that they would also need to be sheltered from winter wet and damp in addition to frost.
Geraniums can be cared for like annuals by being dug out in the fall, composted, and then replaced with fresh plants the following year. The appropriate care and attention, however, will enable you to winterize geraniums, keeping them alive throughout the winter so they can bloom once more the following year.
According to David Taylor, vice chairman of the UK Pelargonium and Geranium Society, “Keen enthusiasts keep their pelargoniums in growth during the winter and continue to feed and water but a few key points can be undertaken by anyone to keep your pelargoniums (geraniums) alive throughout the winter” (opens in new tab).
Pelargoniums are known as geraniums, but these plants are not the same as hardy geraniums or cranesbill, which are a different kind of plant and don’t need to be overwintered.
Do geraniums survive the cold outside?
- Make sure you thoroughly inspect your geranium plants before bringing them inside for the winter. Look for symptoms of pests and illnesses like rust and remove any dead leaves or wilting blossoms. Only zonal pelargoniums are impacted by this, but it is becoming more widespread. It arrived in the nation for the first time in 1968, and it does best in the moist summer or fall months. Fortunately, it doesn’t seem to spread to the plants quickly and is simple to treat, so merely plucking the afflicted leaves is an effective management. You might also consider using the fungicide Dithane 945 as a spray.
- Placing your overwintering plants somewhere bright and sunny will help them retain their need for light throughout the winter. Your plants will receive 50% less light if they are placed more than three feet from a window!
- Because your plants continue to thrive throughout the winter, keep the roots moist. While geraniums frequently survive droughts, they rarely flourish. Show plant growers take special care to keep the roots of their plants damp but never soggy during the winter.
- Ventilate as frequently as you can to maintain a dry environment surrounding your plants. Your plants will turn into a moldy, rotting heap if you don’t allow the air to circulate. The greatest electric fan heaters are those that operate automatically since they circulate air while simultaneously raising air temperature.
- Geraniums are fairly inexpensive to overwinter in the greenhouse because they only need to be kept frost-free. To keep temperatures above freezing, however, we do advise utilizing a heater. Set the thermostat on your heater to 5C, which is 41F. The plant will not survive if the stems become frosty! The winter months are a great time to store your delicate pelargoniums in porches, sunrooms, or conservatories.
We hope that we have provided you with enough of tips so that you can continue to enjoy your geraniums year after year. Visit our geraniums hub page, which is brimming with useful resources, for additional details on how to cultivate and take care of these well-liked plants. And do get in touch with us through our social media outlets to share your personal favorites; we’d love to hear from you.
Can geraniums be kept in pots during the winter?
Geraniums can be overwintered inside in three different ways: as a houseplant, as a dormant bare root, or as cuttings. Your decision will be influenced by the amount of room you have indoors and the range of temperatures you can tolerate. Here is a closer examination of each method.
Overwintering geraniums as houseplants
If you want to keep the entire potted plant and have lots of room close to a window that gets bright, direct light, go with this option. A drafty west-facing window would be the ideal place for your potted geranium to spend the winter because geraniums prefer it chilly (55 to 65 F is optimum).
Wash the foliage well with your hose and repot the plant in new potting soil to prevent bringing unwanted pests from outside. You might also use insecticidal soap, which is sold in most garden centers and hardware stores as well as online. Avoid taking the plant indoors if it shows any signs of pests or illness. Only strong plants have a chance of successfully overwintering indoors.
During the winter, keep the soil wet but not damp. No more humidity is required. If the stems begin to sag, pinch them back to keep the plant compact throughout the winter. When springtime comes around, you may start fertilizing once more and transfer the plant back outside as soon as the temperature reliably rises above 50 F.
Overwintering geraniums as dormant bare root plants
This is the most typical way to overwinter geraniums, but it won’t work unless you have a dark, dry place that stays around 50 degrees throughout the winter.
First, dig up your geranium before it freezes and shake the dirt off the roots. To stop mold from forming, let the plant sit and dry for a few days before storage. Before moving onto the following phase, the roots must be completely dry.
The roots should be kept in a dark, dry place that doesn’t get colder than 45 degrees throughout the winter. Geranium roots should be kept at a temperature of 50 F. You can keep them by doing:
- It has been customary for generations to hang the plants upside-down from the rafters;
- placing them on a shelf after wrapping them in newspaper or a paper bag;
- they were put in a cardboard box.
Step 3: Every month or so, look for mold, black leaves, or limp stems at the roots. Remove any plant or root components that are harmful. Most of the stems should endure the winter in good shape. Before re-storing them if they become too wilted, give them a good bath in water and let them air dry.
Step 4: Reviving your geraniums involves cleaning them up, pruning the stems back to healthy green growth, and replanting them in new potting soil about six weeks before your final frost date. Where the new roots will grow, bury the stems two nodes deep. When you notice fresh growth in one to two weeks, keep the plants somewhat dry; after that, keep the soil moist until the plants are big enough to replant outside.
Overwintering geraniums as cuttings
If your light windowsill area is limited or you are concerned that bringing in your entire potted plant would also attract unwanted bugs, this is a nice technique to try. Additionally, it’s a fantastic way to multiply your existing geraniums.
To trim plants, you’ll need:
- a cutting edge.
- Most hardware stores and garden centers sell rooting hormone, which is sold online.
- Use little terracotta or plastic pots, or recycle a clear takeaway container for roasted chicken.
- If you don’t eat chicken, use clear plastic bags to cover the pans.