Iowa’s AMES Beautiful plants like geraniums offer color and life to any landscape. They are not prepared to endure the hard winter weather, though. Geraniums can be brought indoors to overwinter and then replanted in the spring.
Horticulturists at ISU Extension and Outreach can assist with your inquiries regarding overwintering geraniums and how to keep them healthy during winter weather.
How can I overwinter geraniums indoors?
By obtaining cuttings, potting up individual plants, or preserving bare-root plants in a cool, dry place, geraniums can be overwintered indoors. Before the first fall frost, remove plants from the garden (or take cuttings).
How do you take geranium cuttings?
Take three- to four-inch stem cuttings from the terminal ends of the shoots using a sharp knife. Pinch the bottom leaves off each cutting before dipping the base in a rooting hormone. Insert the cuttings into vermiculite or a mix of perlite and sphagnum peat moss as a rooting media. Rooting containers that have drainage holes on the bottom are pots and flats. Just enough to allow the cuttings to support themselves should be inserted into the media. Water the rooting media once all of the cuttings have been placed.
Place a clear plastic bag or dome over the cuttings to stop the plant foliage from wilting after allowing the medium to drain for a few minutes. The cuttings should then be placed under bright light—not direct sunshine. In six to eight weeks, the cuttings should begin to root. Remove the cuttings from the rooting media after they have healthy root systems and plant each rooted cutting in a separate pot. Until spring, keep the potted plants in a window with natural light or under artificial lighting.
How do you overwinter geraniums as potted plants?
Each plant should be dug up carefully and put in a big pot. After giving each plant plenty of water, set the geraniums in a window with natural or artificial light. Geraniums prefer a cool environment indoors. The ideal temperature range is between 60 and 65 degrees Fahrenheit during the day and a little bit lower at night. Plants need watering around every two weeks. By the end of winter, geraniums are likely to grow tall and lanky. Trim the plants back in March. Reduce the geraniums by a third to a half. Within a few days, the geraniums will start to grow once more, and by May, they should be beautiful specimens.
How do you overwinter geraniums as bare-root plants?
The geraniums should be carefully dug out before the first fall frost. Remove the plant’s roots’ soil by shaking them. After that, put one or two plants in a sizable paper bag and keep it dry and cool (45 to 50 degrees Fahrenheit). It might be appropriate to use an indoor porch or an unheated bedroom. Hanging the plants upside-down in a cool, dry area is an another (somewhat messier) option. Eventually, the leaves and the shoot tips will wither away.
Trim or prune each plant in March. Get rid of all the dried-out, lifeless stuff. Return to firm, green, living stem tissue through pruning. After pruning, pot the plants and give them plenty of water. Put the potted geraniums in a window with natural light or next to a light source. March pruning and potting of geraniums should result in lovely plants that may be put outside in May.
How are geraniums reset in the spring?
Geraniums need to be gradually returned to the warm, bright growing conditions in which they thrive after a long winter of low light and chilly temperatures. Moving the pot to the hottest, brightest location indoors in the early spring is the first step in reviving dormant geraniums. The optimal window for breaking the plant’s dormancy is one that faces south or west and is not shaded, but any window that gets 10 to 12 hours of light per day will do. Fill the pot with water until a small amount of it drips into the catch basin. Use sharp pruning shears that have been cleaned with rubbing alcohol to remove any dead leaves or stems.
As soon as the first new leaves show at the tips of the stems, fertilizer should be applied. A balanced 15-15-15 fertilizer or a fertilizer designed for blooming, such as 7-9-5, is advised for feeding, according to Logee’s Plants. Mix one gallon of water and one half teaspoon of fertilizer together. Once nighttime temperatures remain between 55 and 60 degrees Fahrenheit, move the geranium to a warm, sunny, and protected area outside. Grow it in a pot or in the garden, in bright circumstances with midday shade.
How do you rouse sleeping geraniums?
Dormant, full-size geranium plants can be overwintered in the same way as animals hibernate during the winter and then come out of it in the spring.
Steps to Overwintering Dormant Geraniums
- Before the first frost, transplant the geraniums into containers and prune the plant back by about half. Dehydrate the soil in the pot.
- Put a paper bag on top of each plant and turn it over.
- Containers for dormant plants should be kept in a garage or basement that is chilly, unheated, and slightly damp.
- Every few weeks, check the geraniums to make sure the stems and leaves are not shriveling. Spray them with water or mist the roots if they start to show signs of drying out. After that, let the plant thoroughly dry before putting it back in the paper bag.
Reviving Dormant Geraniums
- Relocate your dormant geraniums to indirect light around 6–8 weeks before the final anticipated frost.
- Trim any dead leaves from the plants, and cut stems back to a healthy, green growth.
- Give the potted plants a good soaking and some fertilizer that has been diluted.
How should geraniums be cared for after the winter?
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.
Pruning Geraniums After Winter Dormancy
The optimum time to prune geraniums is in the early spring if you put them into dormancy for the winter or if you live in a region where they lose some of their leaves over the winter.
Take off all of the geranium’s brown and dead leaves. After that, remove any diseased stems. Squeezing a healthy geranium stem will feel firm. Cut down the geranium plant by one-third, paying particular attention to stems that have begun to turn woody if you want a less woody and lanky plant.
Cutting Back Geraniums That are Wintered Alive
The best time to prune geraniums is in late fall or right before you bring them inside, if you intend to bring them indoors. If you do not put your geraniums into dormancy for the winter and they remain green in the ground or in containers year round.
Trim the geranium plant back by one-third to one-half, paying special attention to lanky or woody stems.
How to Pinch Geraniums
In order to make the plant grow more bushy and compact, geraniums are sometimes pruned. You can pinch either newly purchased bedding geranium plants or geraniums that have been overwintered. Pinching of geraniums begins in the spring.
When a stem on a geranium plant reaches a few inches (7.5–10 cm), cut off 1/4–1/2 inch (0.5–1.5 cm) of the stem with a sharp pair of scissors, or even with your fingers. Repeat over all stems. The geranium will be forced to produce two new stems off of the original stem as a result, which will result in a bushier, fuller plant. If you prefer, you can keep pinching geraniums all throughout spring.
Geranium pruning is simple and improves the appearance of your plant. You may enjoy your geraniums more now that you know how to prune geranium plants.
After the winter, when should I repot my geraniums?
It’s difficult to see all your lovely plants and labor go to waste after enjoying your geraniums outdoors all summer and fall! Here are 4 strategies for surviving the winter:
- Bring your geraniums indoors, and maintain them in a place with plenty of sunlight.
- Allow your potted geraniums to go dormant before storing them in the same pot.
- Your geraniums should be dug out and stored bare-root.
- Take cuttings and continue to grow them over the winter.
Let’s go over each choice in more depth. Bring your plants inside before frost, no matter the method. Whenever possible, I try to bring mine inside before the low temperature drops to 40°F (4.4C).
KEEP YOUR GERANIUMS GROWING INDOORS
Geraniums can be brought indoors and kept growing under grow lights or in a sunny window if you don’t want to let your plants go dormant.
The following are some crucial advice before bringing them back inside:
- Get rid of any dead flower stems, brown leaves, and any petals that may have fallen on the leaves.
- Check your plants for insects, and whether or not you find any, spray them with insecticidal soap (link to Amazon) as a preventative measure before bringing them inside.
- Dig your plants up, shake off any loose soil, and plant them into a pot if you need to move them from the ground to a container. Garden soil is too heavy to be used as a filler in the pot. Use a high-quality all-purpose potting mix; a suitable ratio is 3 parts Miracle Gro to 1 part perlite.
- You might want to cut your geranium back to around half of what it was.
- Give your plants the brightest window you can when you bring them home, or put them under a nice grow light.
- Increase light exposure if you notice that growth is sluggish during the winter. You can also pinch the growing ends off to promote branching and bushier growth.
LET YOUR POTTED GERANIUMS GO DORMANT AND STORE OVER WINTER
Since the majority of my geraniums are grown in pots, I always utilize this technique.
I simply move my geraniums to a cool, dark place for the winter whenever the temperatures drop.
They can be kept there until springtime temperatures start to warm up in a cool, dark basement or even a garage. Darkness and low temperatures are essential for dormancy. The optimal range is 7-13C/45-55F. If you can, keep it at or below 60°F.
You should cease watering the plant and let the foliage wither. Not to worry; your plant won’t perish. Simply put, you’re letting it to go dormant.
Geranium plants can endure dry spells because to their sturdy, succulent stems.
Clean up your plants after the foliage starts to fade and turn yellow. Your plants might even start to bloom. Cut them off even though it may be tempting to leave them in order to prevent squandering your plant’s energy.
You might need to water your pots twice or three times during the course of the winter to prevent the canes from dying and shriveling up, depending on your storage circumstances.
Your canes should remain lovely and firm, so keep an eye on them and water them as necessary to maintain the firmness of the stems.
When Should I Bring Geraniums Out of Dormancy?
I’ll restart my geraniums’ growth when the outside temperature is consistently over 40F.
Here are a few potted geraniums that had begun to thrive while they were dormant. This is commonplace.
I now removed the decaying leaves and blossoms (you could also choose to do it earlier).
I like to set the plants in a protected spot outside after cleaning them up (again, make sure that temperatures are consistently above 40F).
If your plant need a larger pot at this stage, repotting is an excellent idea. At this time, I also like to incorporate some Osmocote fertilizer (link to Amazon) into the soil.
If you’re keeping your plant in the same container that it was growing in the previous year, fertilizing now is extremely crucial. The majority of the nutrients will have been used up by the plant, therefore it’s critical to supplement with a quality container fertilizer like Osmocote.
Since the plants were recently taken out of storage, you can see in the shot above that the new growth is a lighter tint. Because the new growth is so delicate, avoid placing your geraniums in direct sunlight just yet to prevent leaf burn.
For a few days in total shadow outdoors, the new growth must harden off before gradually increasing its sun exposure.
DIG UP YOUR GERANIUMS AND STORE BARE-ROOT
Geraniums can also be stored by being dug up from the ground or even out of a pot and kept bare-root, without any soil at all.
If your geraniums were growing in the ground, this procedure is extremely helpful. Here are a few simple steps:
- Shake much or all of the soil off your plant after digging it up.
- Remove any weak or unhealthy canes, along with any brown leaves and all blossoms.
- For two to three days, let your plant air dry in a protected area.
- You currently have a few choices. As instructed in the previous techniques, put your plant in a brown paper bag, clip the top shut, and set it in a cold, dark spot. The plants can also just be hung upside down.
- Soak the roots in water for 1-2 hours a few times over the winter. At this point, remove any soft stems if you find any. At this point, remove any dead leaves as well.
- Put your plants back in pots in late March or early April so they can start growing again.
One year, I actually pulled several geranium plants out of the ground, shook off the soil, and placed some of them in a sizable pot before storing them in the garage for the winter. Many of them survived despite the fact that I completely neglected them until the spring.
TAKE CUTTINGS AND KEEP GERANIUMS GROWING
Finally, you may just take some cuttings from your outdoor plants and grow them indoors on a sunny windowsill if you don’t want to pursue any of the aforementioned approaches.
This is undoubtedly the most compact approach and is excellent if you simply lack the capacity to overwinter larger plants.
Just take the following actions:
- Use a sterile, sharp knife or pruning shears to prune the tips off of your geranium plants. Your cuttings should be approximately 3 to 4 inches long. Avoid making drastic cuts because there is a higher chance of failing.
- Eliminate all lower leaves (make sure the tip of your cuttings still have at least a couple leaves).
- You have two options at this point: dip the cutting in rooting hormone and plant it directly in the ground, or place it in water to root.
If you choose water propagation, you can pot up your cuttings once they develop roots that are approximately an inch tall and put them in a sunny window or under a grow light.
When using a cutting for soil propagation, first dip the cut end of the cutting into rooting hormone as shown in the picture below.
After that, plant them in a tiny pot with potting soil and perlite (I like to use a half and half mixture for rooting cuttings).
While the soil is undergoing rooted, keep it moist. To hasten the rooting process, you could also lay your rooting cuttings on top of a seedling heating pad. The bottom heat is fantastic!