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.
What is the geranium’s optimum temperature range?
Gardeners have traditionally favored geraniums. They smell wonderful, are colorful, and are simple to grow. How to cultivate geraniums in your house and garden is provided here!
(Note: This page is about Pelargonium plants, sometimes known as geraniums or storksbills. This is not a page about “hardy geraniums, also referred to as cranesbills.
Geraniums are normally kept indoors to overwinter, even if they may be kept outside throughout the warmer months of the year. In contrast, if given enough light, they can bloom all year long indoors.
Geranium or Pelargonium? A Case of Mistaken Identity
Early in the 18th century, Dutch traders who were traveling through South Africa brought the plants that we now refer to as “geraniums” to Europe. Botanists misclassified these new plants into the same genus because they resembled the hardy wild geraniums that are already present throughout Europe.
Botanist Carl Linnaeus of Sweden included them in the genus Geranium in 1753. Pelargonium, which refers to the long, sharply pointed shape of their seedpod, was used to reclassify these new “geraniums when it was later revealed that they differed from European geraniums in the shape of their petals, the number of stamens, and other features.
However, people still refer to them by their old common name, “geranium,” even if we really mean “pelargonium.”
- You can grow geraniums as annual blooms or as indoor plants. They can be kept outside in a sunny area throughout the warmer months of the year (between your local frost dates).
- If keeping geraniums as indoor plants, make sure to do so in the late summer or early fall when overnight lows begin to consistently fall below 55F. (13C).
- Pay great attention to the size and color of geraniums when purchasing them. Healthy stems and leaves will not be straggly or discolored on top of them or underneath them. A plant with evident insect indications should also be avoided. Mealybugs, whiteflies, and spider mites are typical indoor plant pests.
- To prevent root rot, put plants in containers with drainage holes.
- When planting in pots, use a well-draining potting mixture rather than heavy, clayey soil. Geraniums dislike being planted in mucky, compacted soil.
- Place the plants where they will receive 4-6 hours of sunlight per day for the best bloom.
How to Care for Geraniums
- After letting the soil somewhat dry between waterings, water it again well.
- Water plants significantly less throughout the winter, but make sure the roots are not completely dried up. Given a time of hibernation throughout the winter, when they consume less water and don’t grow as much, geraniums thrive. For additional overwintering tips, see the section below.
- Regularly deadhead spent flowers to promote blooming.
- Pinch back the stems to encourage bushiness and prevent legginess.
- Fertilize approximately every two weeks throughout the active growing months. Half-strength a fertilizer that is water soluble When the plant should be dormant in the winter, avoid fertilizing.
- Repotting geraniums can be done in the spring to promote new growth or if they appear to need revitalization.
Overwintering Geraniums
- If they receive plenty of sunlight, geraniums that have spent the summer outdoors can be kept indoors. The sun may not be strong enough in northern regions in late winter to promote buds on some cultivars.
- Lift the plants before the first fall frost (you can find your local frost dates here), and use a sharp, clean knife to shapely prune the stems back to about 6 to 8 inches. In the low-sunlight environment they are about to enter, they shouldn’t have to maintain substantial amounts of leaves. A simple technique to increase the number of your plants is to save a few stems for rooting.
- Place the “mother plant” in the smallest pot you can find—just big enough to hold the roots—and fill it with ordinary potting soil.
- The plants should be kept in the shadow for a week before being moved to a sunny location and kept cool.
- Geraniums thrive in temperatures between 50 and 60 degrees Fahrenheit (10 and 16 degrees Celsius) at night during the winter, but they can also withstand lows of 32 degrees Fahrenheit (0 degrees Celsius) and highs of 80 degrees Fahrenheit (27 degrees Celsius), provided they are kept relatively dry.
- Cut off all the old leaves when the spring growth begins.
Keeping the new growth alive is the only challenge that can compare to getting it to appear. Here is some assistance with that:
- Only offer tiny quantities of water when the leaves begin to droop. Don’t feed or fertilize the plants. These plants must have some downtime.
- Pinch back your overwintered geraniums in February if you want them to bloom by Memorial Day. Take the plants outside and move them to beds or pots, as you like, once warm weather returns and all threat of frost has passed.
- Containers are ideal for growing the Common or Zonal Geraniums (Pelargonium x hortorum) (as well as outdoors).
- Hanging baskets, window boxes, and containers are all extremely popular places to use Ivy-Leaf Geraniums (Pelargonium peltatum).
How to Root Stem Cuttings
The majority of geraniums readily take root from stem cuttings when placed in soil, sand, water, perlite, or another rooting medium.
- Make a slanted incision 4 inches below the tip of the stem, above the node where the leaves emerge, with a clean, sharp knife. Cut the grass immediately below a node. Remove all except two or three leaves, any buds, and the stipules that resemble leaves at the base of leaf stalks.
- To ensure that the cut end of the stem will seal and not rot, roll the stem cutting in newspaper or place it in the shade for 24 hours.
- Place the stem in a wet rooting media container and keep it there for two days in a warm, shaded area. Give the cutting indirect sun after that. Just as needed, moisten the medium.
- Apply crushed geranium leaves to small cuts to halt the bleeding.
- Scarlet geranium is the flower that speaks of foolishness. More floral meanings can be found here.
- You won’t have to worry about those bothersome bugs because geraniums are known to be harmful to Japanese beetles.
- Keep geraniums out of the reach of curious youngsters and animals (cats, dogs) as they might cause indigestion or vomiting.
Low light, overexposure, and underwatering are common issues. Yellowing leaves are a sign that you are watering your plants either too little or too much. Try to water the geraniums evenly in this situation, and transfer them to a more sunny location.
Are geraniums resistant to 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.
What temperature should be used when bringing geraniums inside?
Geraniums do best in climates between 65 and 70 degrees Fahrenheit during the day and 55 degrees Fahrenheit at night. Horticulturists at the University of California claim that scented geraniums only require four hours of sunlight each day. Install a fluorescent light a few inches above the plants if you are unable to provide them with this. When you bring your potted plants inside after it gets below 45 degrees Fahrenheit, the sudden warmth may shock them, turning their leaves yellow and making them fall. Bring the plant indoors for a while before it becomes cold outside, ideally at night, to prevent this. Each day, gradually lengthen the time. This will ease the plant’s transition and minimize major stress. Give the plant more care and ensure that it receives the right amount of water, light exposure, and trimming until it recovers if it still exhibits indications of shock.
When is it too chilly to leave geraniums outside?
Grow geraniums as indoor houseplants or annuals outside their hardiness area. Geraniums can endure cooler temperatures and even light frosts, but when temperatures dip below 20 degrees Fahrenheit, they are subject to harsh lethal freezes, which can cause freeze damage and even lead to plant death. The minimum temperature for geraniums in Celsius is -7 degrees.
When can you plant geraniums outside?
Wish your life had a little more carefree beauty? Plant some geraniums, maybe. Geraniums are beautiful and low-maintenance plants that belong in planters, planting beds, and perennial borders.
Geraniums can be divided into two major groups. Zonal, fancy-leaf, ivy, perfumed, and Martha Washington (or regal) varieties of annual geraniums (Pelargonium species), which often only live for a year, are some examples. Perennial geraniums (Geranium species), which bloom continually from spring to summer, combine striking foliage with attractive blooms that emerge intermittently or continuously.
Where to Plant Geraniums
You must be aware of the type of geraniums you have in order to select the ideal planting location. With the exception of the ivy geranium, which thrives in mild shade, most annual geraniums require a location in full sun. On the other hand, depending on the variety, perennial geraniums can grow in either sunlight or shade. In the country’s southern and western regions, both types profit from shielding from the sun during the warmest time of the day.
What Kind of Soil to Use for Geraniums
Geraniums grow best in healthy, well-draining soil, which is ideal for both perennial and annual geraniums. Improve soil drainage and quality when growing geraniums in planting beds by adding 3 inches of Miracle-Gro Garden Soil for Flowers to the top 6 to 8 inches of native soil. When growing geraniums in pots, Miracle-Gro Potting Mix should be used because it is light and fluffy. For the ideal planting medium, combine garden soil and potting soil in equal portions, or fill raised beds with Miracle-Gro Raised Bed Soil.
How to Plant Geraniums
Starting with young plants, such as the premium geraniums from the Miracle-Gro Brilliant Blooms collection*, is ideal (and simplest). Geraniums, both annual and perennial, benefit from warmth, so postpone planting in the spring until all risk of frost has passed. Once the summer heat subsides in the fall, you can also plant perennial geraniums. Try planting perennial geraniums from late fall to early spring in areas with mild winters.
Geraniums range in height from 4 to 48 inches tall and 6 to 36 inches wide, depending on the variety. For information on the recommended spacing for your type of geranium, consult plant tags. Use a pot that is at least 10 inches across for annual geraniums or at least 12 inches across for perennial geraniums when planting geraniums in pots.
Geraniums should be watered thoroughly after planting, giving the root ball and surrounding soil time to absorb the water.
How to Water Geraniums
Check the soil once a week for annual geraniums, and water when the top inch is dry. During their initial growth season, keep newly planted perennial geraniums in continuously moist soil. With the exception of periods of extreme drought, perennial geraniums can typically thrive on rainfall after they are established.
How to Mulch Geraniums
After planting geraniums, cover the area with a 2- to 3-inch layer of mulch to help keep the soil moist and to prevent weed growth and sun exposure. Use Scotts bagged mulch, chopped leaves, pine straw, or another material that is easily obtainable in your area.
How to Feed Geraniums
Your plants receive an excellent starting dosage of nutrients when you start with rich, nutrient-rich soil. However, you should also feed them frequently all season long for maximum results. Apply Miracle-Gro Shake ‘n Feed Rose & Bloom Plant Food to your geraniums a month after planting to give them the extra boost of nutrition they require for magnificent blooms. Make sure you adhere to label directions.
How to Grow Perennial Geraniums
Even in the coldest climates, perennial geraniums don’t require particular care to survive the winter. After the initial flower flush, cutting perennial geraniums back by around one-third can encourage more blooms. Cut stems back as necessary if hardy geraniums like “Rozanne” or “Pink Penny” spread out too quickly and widely. These vining geraniums can have up to two-thirds of their length removed, and the plants will still grow back. To encourage new growth and prevent wilted leaves, prune cranesbill geraniums to 2 to 4 inches height after flowering.
How to Use Geraniums
Annual geraniums are excellent at stealing the show in planters and flowerbeds. Regal geraniums can resist cool weather and form lovely hanging basket plants, making them an obvious choice for planting in the early spring. Ivy geraniums are very stunning. Geraniums with aromatic leaves are strong in containers and form a lovely patio display where the leaves may be stroked and enjoyed.
In gardens with some shade, perennial geraniums add much-needed color and can thrive next to mature trees. While mid-size perennial geraniums go well with lanky shrubs, shorter perennial kinds create beautiful ground covers.
Are you prepared to begin cultivating geraniums? To learn more about a product, to buy it online, or to locate a retailer near you, click on any of the product links above.