Geraniums are popular garden annuals or perennials grown for their vibrant flowers and lobed leaves. Both annual geraniums (Pelargonium) and hardy or true geraniums (Geranium) are common in landscapes. Geranium flowers can be blue, purple, pink, white, red, or bi-colored. Many varieties of geraniums even have colorful or variegated leaves. Depending on the species, geraniums can bloom from spring till fall with showy umbels or cymes of flowers. Hardy geraniums will overwinter in zones 3-8. These perennials are excellent for woodland and shade gardens, mixed borders, and cottage gardens. Many species of hardy geraniums can be used as flowering groundcovers. Annual geraniums are hardy to zones 9-11, where they work well in containers, cottage gardens, and borders.
Geraniums are relatively low-maintenance, only needing to be deadheaded for additional flushes of blooms. Annual geraniums can be planted in full to partial sun, whereas hardy geraniums can handle more shade. All geraniums need somewhat moist, well-drained soil that dries out in between watering. For hardy geraniums, oftentimes rainfall is enough to ensure that these perennials are sufficiently watered. Geraniums benefit from slightly acidic, compost-rich soil. Geraniums grow up to 1-2 feet tall and wide, offering plenty of room for companion plants.
Shrubs To Plant With Geranium
Shrubs add structure to the landscape, including during winter when geraniums are dormant. For companion planting with geraniums, choose flowering shrubs that grow well in full, dappled, or partly shady sites. Sweetspire (Itea virginica) and pepperbush (Clethra alnifolia) bloom in late spring and summer when most geraniums are flowering. Usually growing from 4 to 6 feet tall, both of these shrubs allow plenty of room for geraniums to be interplanted.The abundant white spikes of flowers from sweetspire and pepperbush complement the spherical or symmetrical clusters of geranium flowers.
Another great shrub for shade is hydrangea, with several species and cultivars that will look wonderful when planted with geraniums. Try growing geraniums with fruiting shrubs such as beautyberry (Callicarpa). The strikingly purple fruits of this shrub remain on the plant from late summer through winter, offering a nice contrast to fall-blooming geraniums along with winter color once geraniums are done blooming.
Perennials To Plant With Geranium
For a carpet of blooms in spring to early summer, grow geraniums with flowering perennials such as phlox (Phlox divaricata or Phlox subulata), columbine (Aquilegia), or Jacob’s ladder (Polemonium). These perennials bloom at the same time as hardy and annual geraniums, providing a showcase of colorful blossoms in partial to full shade gardens. Once these plants have finished blooming, keep the flowers coming with summer-blooming plants like astilbe or summer phlox (Phlox maculata) and fall-blooming plants like asters (Symphyotrichum sp). Complete your perennial design with ferns, which thrive in similar conditions as geraniums. Evergreen ferns like Christmas fern (Polystichum acrostichoides) will ensure that interest remains even through winter.
Annuals To Plant With Geranium
Both hardy and annual geraniums look stunning when paired with colorful annuals, which allows you to try out new designs year after year. Plant geraniums with low-growing, spreading annuals like lobelia and alyssum to create a groundcover with an abundance of blooms. Shade-loving annuals such as begonias and impatiens are an excellent choice for planting with geraniums on shadier sites. Even annuals that prefer more sun, such as petunias and celosia, work well with geraniums for a diversity of bloom colors and shapes. All of these annuals can bloom from spring till frost in optimal conditions, ensuring long-lasting blooms in your garden.
Best Companion Plants For Geranium in Containers
Acting as both a thriller and a filler, geraniums allow for many container designs and combinations. Choose plants that grow best in well-drained potting soil. Grow geraniums with trailing, or spilling plants, such as bacopa, calibrachoa, petunias, alyssum, and lobelia for a full, vibrant look in planters. Geraniums can be planted as a focal point for hanging baskets, with trailing annuals spilling over the edge. Geraniums can also be planted with foliage plants, like coleus, coral bells, and ornamental grasses for a diversity of textures in containers.
Plants Not To Grow With Geranium
Although geraniums can be grown with a wide variety of plants, there are some things to consider when growing geraniums with other plants. While many species of hardy geraniums can handle full shade, annual geraniums grow best in full or partial sun. Therefore, do not plant annual geraniums under the shade of tall or overhanging trees and shrubs. Doing so will result in poor growth and fewer flowers. Additionally, do not plant geraniums with plants that require dry or wet soils, as geraniums prefer something in between.
Best Plants To Grow With Geranium
The best plants to grow with geraniums are plants that like well-drained soils in full to partial sun. Complement geranium’s flowers with shrubs such as pepperbush, sweetspire, and hydrangea in addition to herbaceous plants such as phlox, columbine, Jacob’s ladder, petunias, and begonias. Extend seasonal interest with plants like beautyberry, asters, and long-blooming annuals like alyssum, celosia, and lobelia. Grow geraniums with coleus, bacopa, grasses, and calibrachoa in containers for a diverse, complete potted garden.
Lauren Youngcourt - Published 11-22-2023