How to Grow and Care for Perennial Geranium

Coming in a huge range of shapes, colors, and sizes, perennial geraniums, also called cranesbill geraniums, are beautiful garden plants. However, don't confuse them with annual geraniums, which aren't even related (those are in the genus Pelargonium). There are over 300 species and varieties of perennial geraniums, so it's easy to find one to suit your needs. The plants are short—usually less than 12 inches, although some varieties reach 18 inches—and are ideal for groundcovers and border gardens.

Do you have small nooks and crannies to fill? There's a geranium for that. Looking for a flowering groundcover to spruce up a shady spot? There's a geranium for that, too. No matter your yard's conditions, you're bound to find a perennial geranium that will work. 

Where to Plant Perennial Geraniums

Most perennial geraniums thrive in areas where they can go through a dormant winter chill, so they are most often grown in Hardiness Zones 3–9. The winter chill requirement makes them unsuitable as houseplants, but you can grow them in containers outside and move the containers to a sheltered area outside for overwintering.

Perennial Geranium Care Tips

Light

As a whole, perennial geraniums grow happily in full sun to part shade. Many varieties also do fine in more shade, but they may produce fewer flowers.

Soil and Water

Perennial geraniums can handle just about any soil, but they appreciate well-drained soil and will sulk if they stay too wet. If the soil is clay, amend it with compost or potting soil.

Fertilizer

Unless the soil is poor, perennial geraniums don't usually require fertilizer. However, an annual application of a balanced granular formulation, such as a 10-10-10 product, in early spring before the plant blooms is appreciated. A 2-inch layer of compost is an acceptable alternative to a purchased product.

Pruning

After they're done blooming, geraniums benefit from being sheared back or deadheaded. Plants that bloom on longer stems can be cut down to the basal foliage growth at the bottom of the plants. This will help encourage a new flush of growth and keep them from looking too messy. It may also give you a smattering of rebloom on some species.

Pests and Problems

The only real problem that you might see with perennial geraniums is powdery mildew. This fungus grows on the leaves and looks like a fine, white powder. Powdery mildew is relatively harmless but can slow your plants down and look unsightly. The best way to take care of this problem is to ensure that your geraniums have good air circulation, so don't crowd them in with other plants. Also, keep leaves as dry as possible and avoid overhead watering to prevent the mildew from spreading. If you continue to see this each year on the same plant, try moving it to a more sunny spot. Finally, clean up any leaf debris around plants once they die back in the fall.

How to Propagate Perennial Geraniums

There's no shortage of ways to propagate perennial geraniums, although some of them take longer than others. If you collect or buy seeds, be prepared to wait a couple of years for blooms. If you don't want to wait, root stem cuttings in water, take semi-ripe wood cuttings, or divide the parent plant, all of which have the potential to flower the following year.

Flowers and Foliage

In both foliage and flower, perennial geraniums offer a variety of colors to choose from. The blooms come in shades of pink, purple, and even blue. A few offer starry white flowers, too. Along with the many shades, the blooms often have deeper colored veins radiating from the center like hand-painted whiskers. Perennial geraniums bloom in early to late spring and keep blooming through mid-summer. However, there are a few varieties that bloom into fall.

Many perennials are primarily grown for their blooms because their foliage doesn't offer much interest. Geraniums, however, can have gorgeous foliage. Depending on the species, many have deeply lobed and dissected leaves. Some come in colors such as gold, burgundy, bronze, gray, and green. Toward the end of the growing season, several species also put on a display of fall colors, showing off orange, red, and yellow.

Types of Perennial Geranium

Perennial geraniums are extremely tough and adaptable plants. Here are a few of our favorites.

Bloody Geranium

Geranium sanguineum makes 1-foot-tall mounds of foliage that becomes golden in fall. Vibrant magenta flowers cover the plants in late spring. It tolerates hot weather well. Zones 3-8

Bigroot Geranium

Geranium macrorrhizum makes a fine ground cover and tolerates dry, light shade. The aromatic 6-inch-wide leaves take on splendid fall color. Bright magenta flowers appear in spring; several less strident cultivars are available. Zones 4-8

Madeira Cranesbill

Geranium maderense, crowned with 4-inch-wide flowers, is a showstopper. Its massive leaves are spectacular, too. Zones 9-11

'Johnson's Blue' Geranium

Geranium 'Johnson's Blue' is a long-blooming variety with 2-inch bright blue flowers. It grows to 18 inches tall. Zones 4-8

'Ann Folkard' Geranium

Geranium 'Ann Folkard' has yellowish-green foliage on 2-foot-long scrambling stems that weave among other plants. In midsummer into fall, bright magenta flowers punctuated with black veins and eyes bloom freely. Zones 5-9

'Brookside' Geranium

Like an improved 'Johnson's Blue', geranium 'Brookside' provides loads of blue flowers almost all season long on much tidier plants. Zones 5-7

Striped Bloody Geranium

Geranium sanguineum var. striatum is a long-blooming selection that grows only 4 inches or so in height. In spring, it's covered with pale pink flowers striped with darker veins. Zones 3-8

'Rozanne' Geranium

Geranium 'Rozanne' blooms June to frost with silvery mottled foliage on spreading plants that can grow 3 feet wide. Zones 5-9

Mourning Widow Geranium

Geranium phaeum bears nodding dark purple blooms in late spring over attractive hand-shape foliage. Zones 4-8

Perennial Geranium Companion Plants

Astilbe

Astilbe brings a graceful feathery note to moist, shady landscapes. In cooler climates in the northern third or so of the country, it can tolerate full sun provided it has a constant moisture supply. In drier sites, however, the leaves scorch in full sun. Feathery plumes of white, pink, lavender, or red flowers rise above the finely divided foliage from early to late summer, depending on the variety. It spreads slowly over time when well situated. Most commercially available types are complex hybrids.

Daylily

Daylilies are so easy to grow you'll often find them in ditches and fields—escapees from gardens. Yet they look delicate, producing fabulous trumpet-shaped blooms in myriad colors. There are around 50,000 named hybrid cultivars in a range of flower sizes (the minis are very popular), forms, and plant heights. Some are fragrant. The flowers are borne on leafless stems. Although each bloom lasts a single day, superior cultivars carry numerous buds on each scape, so bloom time is extended, especially if you deadhead daily. The strappy foliage may be evergreen or deciduous.

Iris

Iris, named for the Greek goddess of the rainbow, comes in a rainbow of colors and many heights. All have classic, impossibly intricate flowers. The flowers are constructed with three upright "standard" petals and three drooping "fall" petals, which are often different colors. The falls may be "bearded" or not. Some cultivars bloom a second time in late summer. Some species prefer alkaline soil, while others prefer acidic soil.

Veronica

Easy and undemanding, veronica is eye-catching in sunny gardens for many months. Some have mats with loose clusters of saucer-shaped flowers, while others group their star or tubular flowers into erect tight spikes. A few veronicas bring elusive blue to the garden, but more often, the flowers are purplish or violet blue, rosy pink, or white. Provide full sun and average well-drained soil. Regular deadheading extends bloom time.