The Blood-Geranium (Geranium sanguineum) is a hardy perennial valued for its long-lasting color and robust nature. Commonly called the Bloody Cranesbill, this plant is frequently used as a spreading groundcover, but its compact growth habit makes it an excellent candidate for container cultivation. Growing this true geranium in a pot allows gardeners to feature its striking color palette prominently on patios or balconies. The common name refers to the deep magenta or carmine flowers that bloom prolifically and the dramatic, blood-red foliage color it develops in autumn.
Identifying the Bloody Cranesbill
Geranium sanguineum is a member of the Geraniaceae family. It is important to distinguish this hardy perennial from the tender plants often sold as “geraniums,” which belong to the genus Pelargonium. The true geranium, or cranesbill, is characterized by its deeply lobed, palmate foliage that has narrow, finger-like segments and forms a dense, mounding clump. The plant typically reaches a height of 6 to 9 inches, with a wider spread of 12 to 18 inches, making it well-suited to container growing.
The magenta, crimson, or deep pink flowers are cup-shaped and appear either solitary or in small groups on long stems, blooming from late spring well into the summer. The “Bloody Cranesbill” name references the flower color and the seed capsule, which is long and slender, resembling the beak of a crane. This physical characteristic confirms its identity as a true Geranium species.
Choosing the Right Container and Soil
Since the Blood-Geranium is a deep-rooted perennial, selecting an appropriately sized container is necessary to accommodate its rhizomatous root system. A pot that is at least 10 to 12 inches in diameter and depth is sufficient for a single mature plant. The container must have adequate drainage holes, as the plant cannot tolerate waterlogged conditions, which quickly lead to root rot.
For the potting medium, avoid using dense garden soil, which compacts easily and restricts aeration. Instead, use a commercially formulated, well-draining potting mix that is moderately rich in organic matter. Incorporating amendments like perlite, coarse sand, or small gravel helps improve drainage and aeration. Providing a quality, well-aerated substrate is important for the plant’s long-term health.
Essential Care Requirements
Potted Blood-Geraniums perform best when placed in a location that receives full sun to partial shade, ideally with at least six hours of direct light per day for optimal flowering. In regions with intense summer heat, placing the container where it receives afternoon shade is advisable to prevent leaf scorch and reduce water stress. Because containers dry out faster than garden soil, watering frequency must be adjusted, ensuring the top couple of inches of the potting mix are allowed to dry slightly between waterings.
When watering, soak the container thoroughly until excess moisture drains from the bottom holes, but never allow the pot to sit in standing water. The Blood-Geranium is a light feeder and does not require heavy fertilization, which can lead to excessive foliage growth at the expense of blooms.
Applying a balanced, water-soluble liquid fertilizer at half-strength every four to six weeks during the peak growing season (spring to mid-summer) is sufficient. Encouraging continuous blooming involves deadheading, where spent flowers are removed to redirect the plant’s energy into producing new buds.
Seasonal Maintenance and Overwintering
Seasonal care often includes a mid-summer shearing to refresh the foliage and prompt a second flush of flowers later in the season. At the end of the growing season, the foliage of this hardy perennial will naturally die back, often turning a rich bronzy-red before fading completely. It is recommended to leave the dead foliage in place until early spring, as it provides insulation for the crown and root system during the dormant period.
Overwintering containerized perennials requires specific protection, especially in colder climates (USDA Zones 4 to 8). The most effective method is to move the pot to a cool, unheated, but protected location, such as an attached garage or cold frame, where temperatures remain above freezing but below 40 degrees Fahrenheit.
For plants remaining outdoors in milder zones, the pot should be placed against a sheltered wall and heavily mulched, or wrapped with burlap or bubble wrap, to insulate the roots from sharp temperature fluctuations. Repotting is typically only necessary every two or three years, or when roots begin to emerge from the drainage holes.