How To Grow And Care For Perennial Geranium

You’ve probably grown annual geraniums (in the genus Pelargonium) for years. But those plants are cousins to true geraniums (Geranium spp.) or perennial geraniums. These under-utilized flowers deserve a place in your garden for their hardiness and beauty. Perennial geraniums bloom from spring through summer, and some varieties bloom into the fall. The fast-growing plants don’t require a lot of care, which makes them good for beginners.

Perennial geraniums are low-growing, mounding plants that work well as ground covers, edging plants, or in containers. Also called cranesbill because of the shape of their beak-like fruit produced after flowering, these perennials bloom profusely from late spring to early summer. Pollinators love the delicate flowers that appear on long, graceful stems above the foliage. These perennials are not fussy about soil type, and they grow in full sun to part shade. Deer and rodents generally steer clear of these plants because of their fragrance. Plant them in spring after the last frost so they will become established before hot weather arrives.

Here is everything you need to know about growing and caring for perennial geraniums in the South.

Plant Attributes

Perennial Geranium Care

Perennial geranium is a hardy plant that does well in most garden settings because it thrives in all kinds of soil from sand to clay and needs little care once established. Plant in a location that receives up to six hours of sunlight a day, and provide afternoon shade if you live in a warmer climate. Once established, these only require water during drought conditions. Deadheading is not required, though a quick shearing can rejuvenate leggy growth after blooming.

Light

Give perennial geranium at least four to six hours of direct sunlight. Afternoon shade is okay in hot regions. It tolerates dappled shade, too, but may produce fewer flowers.

Soil

Perennial geranium grows well in all soil types, including sand and clay. When planting in clay, it may help it establish faster if you work some organic compost into the area. It’s not necessary, but you can broadcast spread a granular fertilizer in the spring as well.

Water

Water these plants the first few weeks when getting established. Otherwise, they don’t typically need supplemental watering unless it’s a lengthy drought.

Temperature And Humidity

Perennial geraniums don’t mind the relentless heat and humidity of the South, but they do appreciate partial afternoon shade. They also survive winters well and are hardy in Zones 4 to 8 (USDA) in the South.

Fertilizer

These plants typically don’t require fertilizer unless the soil is poor. In that case, apply a time-released, balanced fertilizer in spring in addition to an annual layer of compost.

Types Of Perennial Geraniums

• G. 'Rozanne': This hybrid clumping variety grows 20 inches tall and 24 inches wide, with nonstop violet-blue flowers throughout the season. It has exceptional heat tolerance.
• G. x cantabrigiense 'Biokovo': This naturally occurring hybrid, discovered in the mountains of Croatia, makes a carpet of 8 to 12 inches tall and 18 inches wide, with delicate pinkish-white flowers in late spring. It’s a fast spreader.
• G. pratense 'Boom Chocolatta': This new hybrid has unique bronze leaves with purple-blue flowers. It tolerates short periods of drought once established. It grows 24 to 26 inches tall and 28 to 30 inches wide.
• G. sanguineum: This plant, native to Europe and Asia, is commonly called bloody cranesbill. It grows 9 to 12 inches tall and 24 inches wide with magenta flowers with darker veins. It blooms in late spring with variable re-bloom throughout the summer.

Pruning

Perennial geraniums are low maintenance once established. Cut them back to the ground after blooming to encourage more foliage and flowers later in the season.

Propagating Perennial Geraniums

Perennial geraniums can be propagated through cuttings, division, or by transplanting new seedlings from the garden. They spread and clump over time, and new growth can be transplanted into pots or other areas of the garden. For healthy growth and flowering, divide the clumps every three to five years in spring.

Propagate Through Cuttings

1. Use clean pruners to take a healthy 3- to 6-inch stem cutting just below a node of the plant.
2. Remove the lower leaves and keep the upper leaves.
3. Plant the cutting directly in soil, or dip the end in rooting hormone and root the stem cuttings in water. Change the water every few days and place the cutting in indirect sunlight.
4. Transplant seedlings by gently lifting them from the soil with some roots intact.
5. Transfer to the desired location.

Propagate Through Division

If the plants need dividing because they’re taking over an area, dig up and divide the clump in the fall. They’re incredibly forgiving about being moved, so don’t be afraid to divide them to make more plants. To divide clumps, follow the steps below.

1. Dig up the parent plant and shake off any loose soil.
2. With a clean knife or garden trowel, cut the clump in half or quarters. Make sure each section has roots and leaves.
3. Plant new sections so the crown is at or slightly above ground level, and water.
   

How To Grow Perennial Geraniums From Seed

Perennial geraniums self-seed and take root easily. Transplant the new seedlings elsewhere in the garden or plant in a pot. Growing them from seed takes a long time. For this method, gather seeds and plant directly in the garden or seed-starting trays in the spring. These plants can take three to five years to flower.

1. To start indoors, fill a seed-starting tray with moist seed-starting mix that is well-draining.
2. Press the seeds lightly into the surface of the soil and cover with a thin layer of soil.
3. Cover the tray with plastic wrap and place in a warm, sunny location.
4. Once seedlings appear, remove the plastic. Transplant the seedlings to small pots once true leaves emerge.
5. Acclimate seedlings to the outdoors before planting them in the spring.
   

Potting And Repotting Perennial Geraniums

You can grow perennial geraniums in pots. They may do better in pots in warmer zones, such as the Mid and Lower South.

To pot, use a 12-inch container with good drainage. Add potting soil mix, and spread out the geranium’s roots as you plant it. Perennial geraniums do not need frequent repotting. Repot when the roots begin to grow through the drainage holes of the container. Divide container plants and repot every three years for new plants.

Overwintering Perennial Geraniums

Perennial geraniums stay semi-evergreen in the Mid and Lower South and mostly die back in the Upper South, reappearing in the spring. There’s no special care required to keep these plants over the winter.

Common Pests & Plant Diseases

Perennial geraniums generally have few issues with pests and diseases, but slugs, aphids, caterpillars, and whiteflies can be a problem. Use insecticidal soap or horticultural oil to treat these pests.

They may also suffer from rust, mildew, and leaf spot. Moist or humid environments can cause rust, and cutting off any affected leaves will help control it. Prevent mildew by spacing plants enough to provide adequate airflow, and water at the roots rather than overhead. Leaf spot can be a problem in moist environments. Apply a fungicide for treatment.

How To Get Perennial Geraniums To Bloom

The most important factor is to give these plants at least four to six hours of direct sunlight per day. You also may get a subsequent flush of flowers if you shear the plants back after the first bloom. If your plants are growing rapidly, it’s okay to shear them back a few times during the season to encourage lush new growth and some additional flowering.

Common Problems With Perennial Geraniums

These are some of the most fuss-free perennials you can grow. But you should watch for yellowing leaves as an indicator of proper care.

Leaves Turning Yellow

This is a sign that the plant isn't receiving enough sunlight. If possible, transplant the plant to a sunnier location where it will get at least four hours of sun per day.

Yellow leaves can also be a sign of too much water. Avoid overwatering by letting the top layer of soil dry between waterings. If in a container, make sure the pot has adequate drainage so the roots are not sitting in soggy soil.