I’ve walked through many gardens in my lifetime, noting how well-maintained and visually interesting they can be. I always thought a garden like that would require more work, time, and space than I could manage.
Having just built a new home on just over three acres of uncharted land, I can now have my own planned-out and gorgeous perennial garden. Because I have my small-scale farm to care for during many months of the year, I need my home garden to be low maintenance yet still lovely and enjoyable. These flowers offer so much variety and will require so little of me that I plan to add many different species to our landscape in the upcoming spring.
Let’s discuss how to plant, grow, and care for hardy geraniums.
Overview
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What Is It?
Hardy geraniums, often called cranesbill geraniums, are herbaceous perennial flowers. They are often used as a flowering ground cover to fill nooks and crannies in landscaping. Not to be confused with annual geraniums, which are oftentimes referred to simply as geraniums, these come back year after year and come in a wide range of color options, heights, and sizes and bloom for 4-6 weeks.
Hardy vs. Annual Geraniums
Hardy geraniums are perennials, while annual geraniums are often grown as annuals.
It’s easy to confuse the hardy type with annual geraniums. The term “geranium” is used loosely to refer to both categories. Here are some facts that may help you remember which is which.
Hardy geranium key characteristics:
- Perennial
- Often called wild geraniums or true geraniums
- Hardy in zones 3-8, very tough
- Spreads slowly via rhizomes
- Difficult to start from seed
- Family Geraniaceae
- Genus Crane’s-bill
- About 300 species
Annual geranium key characteristics:
- Annual
- Often referred to as zonal geranium or simply geranium
- Can be hardy in zones 10-11
- Easy to start by seed
- Often grown in containers. Typically brought indoors for the winter or started fresh each year.
- Family Geraniaceae
- Genus Pelargonium
- About 280 species
- Native to Southern Africa
Characteristics
It is prized for its crane’s bill-shaped seedpod, easy maintenance, and diverse colors.
The hardy geranium is nicknamed Cranesbill due to its unique seedpod that resembles a crane’s bill, a sort of beak-like crook neck. They are sought after for their ease of maintenance, range of color and beauty, disease-resistant cultivars, and extreme hardiness. Its name comes from the Greek term for crane, “geranos”.
There is seemingly a species for every garden, whether you have a large flat area to cover, a rock wall you’d like to fill in, or are looking for something to suppress weeds, each variety adding a unique burst of color. The Chicago Botanic Garden evaluated 111 species, focusing on those that do well in northern gardens, and published their findings.
Appearance
Hardy geraniums boast diverse foliage and colorful blooms, varying in height and spreading capabilities.
The foliage can be green, blueish-green, or even yellow and orange, with 3-7 lobes each. Their 5-petaled flowers range from white to pink and purples to violets and dark blues. They don’t get much taller than three feet and can spread out up to three feet, making some cultivars great ground covers.
While some hardy geraniums are known for their evergreen and grown covering abilities, other species are known for their brilliant blooms and bright fall foliage.
Reproduction
They release seeds in crane-shaped pods that self-disperse but seldom become invasive.
About 3-5 weeks after blooming, the cranesneck is ejected from the center of the flower, containing one seed each. If left to dry out, the seeds are exposed and easily catapulted 10-30 feet from the mother plant to start a new generation. Although they easily self-seed, hardy geraniums rarely become invasive.
Native Area
Also known as cranesbills, these flowers are native to Eastern North America.
Cranesbills grow widely across Asia, Europe, New Zealand, and North America, but they’re native to Eastern North America, growing wild on roadsides and in woodland areas.
How to Grow
They’re not called “hardy” for no good reason! Hardy geraniums are low-maintenance and very forgiving.
Light
They thrive in full sun to partial shade, while few withstand full shade well.
Hardy geraniums prefer full sun to partial shade. Some tolerate full shade, but it’s not recommended or appreciated by most cultivars.
Water
Provide supplemental watering until plants are established.
Water well when newly planted. Once established, minimal watering is required. Although most species are drought-tolerant, you should also take special care during extreme heat and drought conditions. Deep root watering is preferred to overhead to help prevent disease.
Soil
The plants thrive in well-draining, slightly acidic to neutral soil.
Well-draining, slightly acidic to neutral, and composted soil is preferred, but cranesbill will tolerate moderately poor and even clay soils. Peak performance occurs in well-draining soil over any other factor.
Spacing
Consider its mature width before planting, aiming for one to three feet.
Check the width your plant will be at full maturity before planting it. One to three feet is advised as most will spread out quite a bit, and ample airflow is important for preventing disease.
Also, proper nutrients are needed for peak performance and long-lasting blooms. Remember, you can split them later or move them to a new place in your garden if the spacing isn’t ideal.
Temperature and Humidity
Hardy geraniums thrive in temperatures between 65-75°F, avoiding extreme heat and high humidity.
Ideal conditions include daytime temperatures of 65-75° and nighttime temperatures of 50-60°. These plants don’t love extreme heat or humidity, and even though most mildew issues provoked by high humidity levels aren’t life-threatening, it’s best to avoid them.
Fertilizing
They thrive with minimal care, requiring a spring feeding of well-balanced fertilizer.
Hardy geraniums don’t need much but will benefit from a spring feeding of granular, well-balanced, slow-release fertilizer such as a 15-15-15. If your soil is healthy, this should be enough to support your plants. However, a late-season feed may encourage a fall bloom.
Mulching
Mulch hardy geraniums after spring feeding to reduce weed growth and retain moisture.
In the spring, mulching your hardy geraniums after your annual feed will help keep weed pressure down and help your plants retain moisture. Shredded leaves, straw, pine straw, or woodchips can be used. Cover thoroughly, but allow the plants to breathe.
Cutting Back/Deadheading
Regularly trim old foliage and flowers during blooming for optimal appearance.
Depending on the cultivar you are growing, most hardy geraniums should be trimmed of old and dried-up foliage and flowers throughout the blooming period to keep them looking their best. Some prefer to be cut back or deadheaded after their blooming period.
Some cultivars can be encouraged to bloom a second time by deadheading, so take note of that before fully cutting them back. Also, if you’ve selected a cultivar with showy foliage in the fall, you won’t want to miss out on that.
Propagation
Hardy geraniums can be propagated both by seed or through division by digging up a clump or taking cuttings from either the roots or stems.
Growing from Seed
Winter sow hardy geranium seeds from November to February in a pot of moist soil.
While you can grow cranesbill from seed, it takes several years and is only recommended for experienced growers. Winter sowing these seeds anytime from November to February is a great option because they need about two months of chilling to germinate.
Sow seeds in a pot or milk jug of moist but not soggy soil, sand, or a mix of seed-starting mix with vermiculite. Water well and put them in an area of your garden that’s protected from critters, strong winds, and harsh snow. Germination can take anywhere from 2-6 weeks, so be patient.
Check on them during warm spells in the spring, cracking the lid to provide ventilation. Hardy geraniums don’t usually flower until the second or third year after germination.
Division
Splitting cranesbill every few years helps maintain healthy growth.
Find a gardening friend with a plant they’re willing to split, or follow these recommendations if you have hardy geraniums you want to divide. This will allow you to expand into other parts of your garden easily.
Cranesbill should be split every three to five years to rejuvenate the root system and keep it in peak condition. Division can be done after cutting back the plant in the fall or spring before new growth begins.
Find a good division point by locating the base of the plant and its roots. You can quarter or half an established plant. Cut it evenly using a sharp trowel or spade, leaving enough roots for both clumps to regrow and succeed. You can also use a gardening fork for this step, separating the clump where the tines cut into the roots.
Then, pot up the new clump with fresh soil and transplant it to its new home in your garden, leaving enough space for it to spread out as needed. Make a hole large enough to fit the root ball and plant it so the crown is right at the soil surface. Water it well upon transplant.
Root Cuttings
Propagate hardy geraniums through cuttings from a friend’s plant or your own.
That same friend may allow you to take cuttings from their plant to help you get some going in your garden. Or, if you already have well-established hardy geraniums, they take well to cuttings, which can be used to expand your garden in the spring.
Armenia cranesbill (G. psilostemon), which has been called one of the most hardy in its genus, as well as Bloody cranesbill (Geranium sanguineum), both tolerate cuttings very well.
How to take cuttings from hardy geraniums:
- After your plants have bloomed and been cut back for the season, using a sharp trowel or spade, dig up the clump of your plant.
- Shake off excess soil to expose the roots.
- Near the crown, locate healthy-looking, white, chunky roots about pencil thickness with nodules. These nodules will form new sprouts.
- Cut lengths of about 2-4 inches long with a clean, sharp knife, taking note of the top and bottom.
- Prepare your pots with fresh, moistened soil and a little bit of compost.
- Add one cutting vertically to each pot so that the top of the roots is level with the soil.
- Add a layer of vermiculite or perlite if desired to help maintain moisture.
Water the pots well and place them in a well-ventilated area, outside of the harsh elements, or in a basement or garage protected from critters. Label them for future reference. Because they’re hardy perennial, they’ll be just fine outside. Transplant them the following spring or hold them over until the following fall.
Stem Cuttings
Taking stem cuttings for plant propagation is most successful during the early morning hours.
Stem cuttings can be taken at any time of the growing season, but best if done in the early morning before the sun is hot. Using a sharp, clean knife, cut stem pieces below a node about 2-3 inches long. Strip off any flowers or seed pods, but allow two to three leaves to remain.
In a large cell seed tray or containers filled with composted seed-starting or potting soil, dibble small holes and transplant the stems into the cells, tucking them in snugly. Optionally, sprinkle vermiculite over the top to help hold in moisture.
A strong root system should form within 6-8 weeks. Step them up into larger containers as needed. Plants can be transplanted in the spring when the soil can be worked, or you can allow them to grow in protected space.
Transplanting
Optimal transplant timing for hardy geraniums is in the spring or fall.
Transplant hardy geraniums in spring or fall. If you have taken cuttings, doing so in the spring will give them the whole season to establish a strong root system and hopefully bloom the following year.
Location
This species thrives in various placements such as borders, under trees, or in cottage gardens.
Hardy geraniums will prefer a spot that receives full sun to partial shade. Although foliage can thrive in a shady spot, you may not receive any or an abundance of blooms. They are particularly popular in landscaping along borders, under small trees, as part of a cottage garden, or between rock walls. Varieties with scented foliage may be nice along an outdoor seating area.
Popular Varieties
There are over 300 species of cranesbill, ranging in color, bloom time, growing zones preferred, height, and size. Many cranesbills were created in nurseries by crossing different breeds for various desired traits.
Here are a few of my favorites that I recommend you try and why I think they’re great. Many of these have received the Award of Garden Merit of the Royal Horticultural Society.
‘Patricia’
‘Patricia’ is a stunning, low-maintenance magenta flower with dark green foliage.
This stunning magenta species has a black star-shaped center with dark veins feathering atop dark green foliage. ‘Patricia’ resembles a mini petunia, featuring similar cup-shaped blooms, and grows to two to three feet tall.
Known for its long bloom time from late spring to mid-summer, ‘Patricia’ grows without much effort in zones 4-8. Once established, it performs well in drought conditions, plus it attracts butterflies and deters deer to boot!
‘Czakor’
‘Czakor’ is a fragrant, low-growing species with mat-like leaves and vibrant hot pink flowers.
This species produces fragrant leaves, making it a nice option to plant near a patio or zen garden. It grows just about a foot in height, but its mat-like leaves can spread up to two feet, making it a fantastic ground cover option. ‘Czakor’ blooms clusters of small, dark hot pink flowers.
The leaves of ‘Czakor’ turn a lovely orange color in the fall, and the plants should just be trimmed. If you fully cut them back, you’ll miss out on the fall spectacle.
‘Mrs. Kendall Clark’
This is a whimsical, self-seeding flower with pale lilac-blue petals.
She’s the perfect option if you’re going for a magical, whimsical feel in your garden. Her small, fairy-like pale lilac-blue petals feature white feathering and dark green lobed leaves that bloom in spring to early summer.
‘Mrs. Kendall Clark’ self-seeds and spreads easily, so it is best used in borders, under shrubs, or as part of a cottage garden. This variety requires very little care and grows to be two to three feet. Her charm is sure to delight in your garden.
‘Kashmir White’
‘Kashmir White’ presents delicate, translucent white flowers with pink veins.
This variety features a delicate white, almost translucent flower with pale pink veins about two inches wide, upward-facing, and saucer-shaped. The leaves are deeply lobed, and the plant will grow to about two feet tall. While it typically only blooms from late spring to midsummer, you can encourage a second flush after the first one by cutting it back and fertilizing.
‘Kashmir White’ does not perform well in hot summers or humid areas. She does, however, tolerate shade better than others. Deer and rabbits shouldn’t bother her.
‘Dreamland’
This is a disease-resistant hardy geranium with pale pink flowers.
Appropriately named for its dreamy pale pink, cup-shaped flowers, this variety is known to bloom from early summer to the first frost! Its greenish-gray leaves offer a nice contrast to the dark pink veined flowers. Cutting back dried-up and old flowered stems and leaves will encourage new growth.
‘Dreamland’ is more disease and pest-resistant than some other hardy geraniums, and butterflies seem to love its runway-esque flower shape. If you’re looking for something very low-maintenance with a long bloom time, she’s the one!
‘Midnight Reiter’
‘Midnight Reiter’ dazzles with dark plum foliage and delicate blue-purple petals.
This showstopper is praised for its uniquely dark plum foliage and small, separated light blueish-purple petals, which bloom from early to late summer. ‘Midnight Reiter’ is perfect for containers, growing to just eight to ten inches tall. Plant it in well-draining and composted soil for best results.
“Crystal Lake’
This variety is a stunning trailing plant ideal for sloped gardens or rock walls.
OK, this trailing variety is a stunner. There’s no other way to say it. If you have a sloped garden or a rock wall that needs some oomph, ‘Crystal Lake’ will trail over, filling in any gaps with beauty. She can even serve as a ground cover if you let her be wild and free. Bright purple veins, in contrast to icy blue-white petals, are striking against neutral rocks and along border walls. Chef’s kiss.
‘Crystal Lake’ may stop blooming in the heat of summer, but if trimmed back appropriately and restimulated, you might see a fall flush.
Potential Problems
Hardy geraniums offer very few big problems, but here are a few you may encounter.
Pests
Geranium budworm causes damage by feeding on young flower buds.
The Geranium budworm or tobacco budworm is the cutworm moth larva and can wreak serious havoc in your garden. They’re about an inch and a half long, range in colors from brown to red to black with vertical black striping, and attack the young buds of flowering plants. They burrow into the stems when they hatch and feed on young buds of flowers. If you notice your plants aren’t flowering or the flowers are deformed or delayed, you may have a budworm issue.
This pesky worm can survive year-round in warmer climates and will remain especially active in greenhouses and protected high tunnels. Hand-pick these in the spring when you first notice them to avoid a second generation. They can overwinter, so it’s important to rid your garden of debris and clean up areas they are tempted to overwinter eggs.
The four-lined plant bug is a common pest affecting perennial flowers. They’re small, greenish-yellow, and feature four black lines that run vertically down their bodies, slightly resembling the cucumber beetle. As nymphs and adults, they will suck the juices (chlorophyll) out of the foliage of young plants, causing light brown sunken spots. In low numbers, they do not cause much damage and, luckily, only produce one generation per year.
Look for their banana-shaped eggs along the stem in the spring. Use insecticidal soaps to control them as nymphs following the recommended application instructions. Cleaning up all garden debris in the fall and spring will help keep this pest away.
Bonus: Most hardy geraniums are deer and slug-resistant!
Diseases
Hardy geraniums are typically resilient, showing resistance against common diseases.
For the most part, hardy geraniums are disease-resistant, but there is always some risk. Here are a few to look out for.
Powdery Mildew
This can quickly spread in warm, dry conditions, particularly affecting hardy geraniums in shadier spots.
While powdery mildew (PM) can start seemingly small and harmless, if conditions are just right and this disease is thriving, it forms mycelia and spreads like wildfire, affecting all parts of the plant. This fungus loves dry, warm weather, so it mostly shows up in the summer.
If you’ve chosen to plant any of your Hardy geraniums in a shadier area, they may be more affected by PM as they won’t dry off as much as their sun-basking counterparts. Fungicides applied when early symptoms are noticed can help control PM.
Downy Mildew
Geraniums suffering from downy mildew display light spots on their undersides and wilting leaves.
Do your leaves have light spots on the undersides? Are the leaves wilting? If so, your geraniums may be infected with downy mildew (DM). This quick-spreading fungal disease can be hidden in overwintered debris, in your soil, or carried in on a humid day from other plants nearby.
It’s important to avoid overcrowding to allow ample airflow and use drip irrigation rather than overhead watering to prevent wet leaves and decrease the disease risk. While prevention is key, DM can also be treated with preventative neem oil or copper fungicide once it’s present.
Bacterial Leaf Spot
Bacterial Leaf Spot is identifiable by dark spots with yellow halos on leaves.
Look for symptoms of small, dark spots on the leaves with a yellow halo. Bacterial leaf spot can spread quickly if left alone, so remove any affected leaves and flowers immediately. Burn or bury the debris. Pseudomonas syringae, which causes the disease, can overwinter in weeds.
Rust
Rust can be controlled with fungicides, but careful label reading is essential.
Rust-colored spores, discolored leaves, and stunted growth may be caused by rust. The fungi causing Puccinia spp. can be controlled with fungicides. Always read labels thoroughly before applying.
Key Takeaways
- There are lots of hardy geranium species to choose from suitable for rock walls, used as weed suppressors, ground cover, added to cottage gardens, or in containers.
- Require very little care and maintenance
- Pollinator-friendly and mostly deer and rabbit-resistant
- Great for beginners and master gardeners alike
- Easy to propagate by cuttings or division
- Highly rewarding
Frequently Asked Questions
Ornamental grasses complement the thick mat of foliage and bright colors of true geraniums in border gardens and add textural interest.
Leaves may turn yellow when your plants have received too much water, either from rainfall or irrigation. Once established, hardy geraniums don’t require much attention, so try backing off on the watering a bit to see if the plant recovers. Ensure proper drainage in the soil or in a container, that it has drainage holes and the soil is not soggy.
Yellowing leaves may also be from a lack of nitrogen. An at-home soil test can help you determine if this is the culprit.
While true geraniums grow larger each year, they only need to be split every 3-5 years, so the growth rate is fairly slow.
Lack of blooms could result from lack of ample sun, over-fertilizing causing too much nitrogen to accumulate in the soil, or soggy soil. If you have a sunnier place with well-draining soil, try moving your plant there. Ensure healthy organic matter levels. Test the soil first to check the fertility.
Final Thoughts
Hardy geraniums deserve a spot in your garden, especially if you’re looking for a high performer who requires very little from you. With a wide range of colors, shapes, and sizes, there is surely something for you.
