Among the most common garden perennials are hardy geraniums, sometimes known as cranesbills. And it’s clear why. They require little care and maintenance, are hardy, easy to grow, and tolerant of a variety of environmental factors.
The bloom color ranges from vibrant to subdued violet, blue, pink, magenta, and white hues, and many have appealing veining in a stronger, contrasting hue. Throughout the summer and well into autumn, several types flower nonstop for months at a time, and some even begin blooming as early as late April. When in bloom, the flowers, which are typically rather small, are produced in such great quantities that they almost completely cover the plants.
Numerous species’ hand-like foliage, which exhibits varied quilting, veining, and color blotching, is also very appealing in and of itself. Additionally, because many of the popularly cultivated kinds are low-growing, they make wonderful ground cover plants due to their dense, carpet-like leaf.
They should not be mistaken with the very similarly related pelargoniums, which aren’t and are primarily used as summer bedding plants, as they are cold- and frost-hardy.
Cultivation
There are kinds that can thrive in direct sunlight, light shade, and even pretty deep shadow. They generally thrive in early morning and late afternoon sun, while some, like Geranium sanguineum and Geranium pratense and their variants, grow well in full light as long as the soil has enough moisture.
Hardy geranium varieties
There is at least one hardy geranium for every garden, every gardener, and every circumstance as there are about 70 species and 700 types to choose from!
Here are the top 10 items that the Royal Horticultural Society suggests:
- Ann Folkard, geranium
- (Cinereum Group) Ballerina named Geranium
- Clarkei Kashmir White Geranium
- Red geraniums
- Theodora Mavis Simpson
- Ingersoll Orion
- The Mrs. Kendall Clark geranium
- Wageningen’s Geranium x oxonianum
- Renardii geranium
- Jolly Bee and Geranium Rozanne (Gerwat)
Planting hardy geraniums
Hardy geraniums can be planted at any time of year, but planting in the fall or winter will ensure that the plants take root effectively and provide an abundance of flowers in their first season. For planting from late autumn to late winter, mail-order vendors often offer bare-rooted plants.
Make a hole that is sufficiently large to readily fit the rootball. Fork in a layer of organic material, such as compost or planting compost, at the bottom of the hole.
Place the rootball in the planting hole, adjusting the planting depth until the rootball’s top is level with the soil and the rootball is planted at the same depth as it was growing initially.
Fill the planting hole with the excavated soil after adding more organic matter to it. To maintain soil moisture and aid in weed control, thoroughly water the area around the tree, then sprinkle a granular general feed over the surrounding soil. Finally, put a 5-7.5cm (2-3in) deep mulch of well-rotted garden compost or bark chips around the tree’s root area.
How to care for hardy geraniums
The majority of hardy geraniums are undemanding, low-maintenance plants.
When the weather is dry during the first year, water thoroughly. To maintain healthy plant growth in succeeding years, watering may be required during extended dry spells.
Late spring mulching around the plants will assist retain soil moisture and control weed growth.
Plants may start to seem messy with sloppy growth after the first early flush of blossoms has faded. After the initial flowering, the majority benefit from a trim to freshen the foliage and promote more blooms. To get rid of the outdated, messy growth, just cut the plants with a pair of shears or secateurs, or more forcefully if necessary, to a height of 5-7.5cm (2-3in) above the ground.
Then feed them with a liquid plant food to promote new growth and additional flowering flushes. After each flowering, pruning and fertilizing can be done again to extend the flowering season of many kinds well into the fall.
With the arrival of colder weather in late autumn, most geraniums’ foliage will start to fade. If you trim the plants’ leftover stems and leaves, they’ll grow new, fresh growth the following spring.
Over time, hardy geranium plants expand, spread, and form enormous clumps. These can be chopped into halves or quarters with a sharp spade. This can be done in the spring when they begin to grow or in the autumn. Every three to five years, divide them to maintain good growth and flowering.
When may hardy geraniums be transplanted?
In order to give the plant enough time to establish its roots before a frost, divide the geraniums in the early spring to early summer. Shake the earth off the plant’s roots by digging it up. Make divisions with a trowel or knife, being careful to include a root section and leaves in each division.
Can geraniums be divided?
Hardy geraniums are clump-forming perennials that can be divided to produce more plants, rejuvenate an overgrown clump, or maintain good flowering. An established plant is divided into multiple sections, each of which has a portion of the roots.
Should hardy geraniums be pruned back?
Hardy geraniums require hardly any maintenance. Rabbits don’t seek them, while slugs and snails prefer to consume other plants. After their initial flowering, they can be trimmed right back to the ground, and the next summer, they will produce new foliage and additional blooms. Avoid cutting back too soon after flowering because some hardy geraniums have lovely autumn leaves.
Propagating hardy geraniums
Hardy geraniums don’t typically need to be propagated because seedlings may be easily removed from the garden and potted up. In the spring, plants can be lifted and divided. Hardy geraniums can be challenging and time-consuming to grow from seed.
Growing hardy geraniums: problem solving
Geraniums that are hardy are generally trouble-free. However, the geranium sawfly larvae have been known to attack them (Ametastegia carpini). These appear to be 12mm long, small grey caterpillars. They leave unattractive lace-like holes in the leaves after they eat them. In your garden, the more resilient geraniums you have, the more probable it is that they will reproduce.
Since they fall off the leaves when the plant is disturbed, the larvae might be challenging to see. The months of May and September see the most activity; the September generation pupates in the soil and spends the winter there before emerging in the spring to deposit eggs on the foliage. Even though the damage can be extremely unattractive, the plant rarely becomes less vigorous as a result. The following steps could assist in keeping them in check:
- Many geranium sawfly larvae overwinter in the soil, therefore clearing away debris and lightly raking the soil beneath vulnerable plants will expose the larvae to the elements, where they will be killed by frost and devoured by birds and other predators.
- From May on, carefully inspect the undersides of leaves for signs of the eggs and larvae and remove them by hand if possible to prevent numbers from growing.
Do tough geraniums thrive in the shade?
Unlike the annual geraniums (which are actually pelargoniums) we buy for porch pots or bedding plants, hardy geranium is a perennial. Hardy geraniums grow in low mounds and bloom in white, red, purple, pink, or blue from spring through October. Some cultivars do perfectly in full shadow, and they will still thrive in part shade. Hardy geraniums also survive dry soil, which is a benefit when growing them under trees. In zones four through eight, they are resilient.
Why aren’t my hardy geraniums blooming?
With the majority of their species being native to South Africa, geraniums (also known as pelargoniums or storksbills) are drought and heat tolerant plants that, under the appropriate circumstances, may bloom all year round in warm regions.
Geraniums don’t bloom because of wet soil, excessive shade, chilly temperatures, and high nitrogen fertilizer. To blossom in the summer, geraniums need well-draining soil, potassium fertilizer, full light, and nights that are regularly warmer than 55F (12C).
To find out why your geraniums aren’t flowering and how to put the best practices into practice so that they bloom to their full potential, keep reading.
What can I grow beside hardy geraniums?
Late spring to early summer, with some flowers reblooming all summer long in hues including white, blue, and pink.
Actually, geraniums aren’t geraniums. The annual flower Pelargonium is what most gardeners mean by geranium. I discuss them in the annuals chapter. In New England, true geraniums are hardy perennials with low growth and free flowering that come in hues like blue, white, and pink. Due to the seedpod’s resemblance to the bill of this bird, they are also known as cranesbill geraniums. The flowers develop above the lobed foliage and bloom intermittently throughout the summer. Deadhead the plant on a regular basis. This rambunctious plant extends out a few feet, but pruning and division control it. Bees and butterflies are drawn to the tiny, cup-shaped flowers.
Grow resilient geraniums all around New England. After all risk of frost has past, plant locally acquired transplants or divisions from a friend’s garden in the spring till early October. Although they will still bloom in partial shade and on clay soils, they grow and bloom best in full sun on well-drained, compost-amended soil. In beds, leave a foot between plants.
Each spring, plant hardy geraniums with a layer of compost and lots of water and fertilizer. Mulch around plant bases to prevent weed growth and maintain moisture in the soil.
If deadheaded and pruned after the initial blooming time, hardy geraniums will produce flowers again. If plants are divided every three to four years, they appear neater and blossom better. Dig up the cluster in the spring and separate out 1-foot-diameter portions for replanting or sharing. One of the most low-maintenance perennial plants you can cultivate in your garden is a hardy geranium. However, they are susceptible to powdery mildew in partial shade or during humid summers. To lessen the prevalence of this illness, keep plants clipped, spaced far apart, and clear away the fallen leaves in the fall.
In the perennial garden, hardy geraniums make excellent filler plants. They can fill in next to plants that have done flowering, like peonies and iris, or they can enhance other summer blooming plants, like roses, daylilies, and coreopsis. This is because they sprawl and flower in the summer. Keep hardy geranium trimmed so they don’t look too untidy if you plant them in the front of your flower bed. More trailing plants can be planted along a wall to cascade over the top.
My preferred hardy geranium variety is “Rozanne. This cultivar bears violet-blue flowers on a 2-foot-tall plant.” “Ann Folkard is a magenta colored flower kind that barely grows 8 inches tall and is ideal in a rock garden or along a wall. Johnson’s Blue is another similarly small blue blooming variation. White blooms grow on 12-inch-tall plants in the album.