How to Plant, Grow, and Care for Hardy Geraniums

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.

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

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. 

Characteristics 

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

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

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

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 

Hardy geraniums prefer full sun to partial shade. Some tolerate full shade, but it’s not recommended or appreciated by most cultivars.

Water

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

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

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 

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 

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

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

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

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 

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

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. 

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 

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 

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

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’

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’

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’

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’

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’

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’

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’

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 

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

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

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

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

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-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.

Frequently Asked Questions

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.