The term “Geri Plant” is a common name for popular garden and house plants, most frequently referring to the Pelargonium genus, widely known as geraniums. While true geraniums (Geranium) are distinct, Pelargoniums’ widespread cultivation led to this interchangeable usage. This article focuses on the care and characteristics of Pelargoniums, the plants commonly called “Geri Plants.”
Understanding the “Geri Plant”
The plants commonly called “Geri Plants” are Pelargoniums, originating from South Africa and Australia, where they thrive in warm, sunny climates. These plants are appreciated for their vibrant flowers and sometimes fragrant foliage. Pelargoniums are evergreen perennials or shrubs, though they are often grown as annuals in cooler climates due to their sensitivity to frost.
Various forms exist, each with distinct characteristics. Zonal Pelargoniums (Pelargonium x hortorum) are recognized by their bushy, upright growth and often a dark, horseshoe-shaped band on their leaves, producing dense, ball-like flower clusters. Ivy-leaved Pelargoniums (Pelargonium peltatum) feature trailing stems and glossy, ivy-shaped leaves, making them suitable for hanging baskets. Regal Pelargoniums (Pelargonium domesticum) display large, showy, often bi-colored flowers with ruffled petals. Scented-leaf varieties offer aromatic foliage with scents like rose, lemon, or peppermint when touched.
Care Guide
Light Requirements
Pelargoniums flourish in abundant sunlight, ideally receiving at least six hours of direct sun daily for optimal blooming. In regions experiencing intense summer heat, providing some afternoon shade can prevent scorching of the foliage and flowers. When grown indoors, a bright, indirect light location is suitable. Sufficient light also helps prevent leggy stems and promotes dense, healthy growth.
Watering
Pelargoniums prefer their soil to dry out between waterings, as they are susceptible to root rot if kept consistently wet. Water deeply but infrequently, allowing the top inch or two of the soil to dry to the touch before rewatering. Plants in containers typically require more frequent watering than those in the ground, especially during warm summer months. During winter, when growth slows, watering should be significantly reduced.
Soil and Potting
Well-draining soil is important for Pelargoniums to prevent waterlogging, which can lead to root problems. A fertile, slightly acidic to neutral soil pH, generally between 6.0 and 7.0, is suitable for their growth. For container planting, a peat-free multipurpose compost or a soil-based potting mix provides an appropriate growing medium. Ensure that pots have adequate drainage holes to facilitate proper water runoff.
Temperature and Humidity
Pelargoniums thrive in warm conditions and are not tolerant of frost. Ideal daytime temperatures range from 65-75°F (18-24°C), with nighttime temperatures around 55-60°F (13-16°C). Temperatures consistently below 50°F (10°C) can cause stunted growth, leaf yellowing, and wilting. Avoid excessive humidity, particularly on foliage, to prevent fungal issues.
Fertilizing
Regular fertilization supports vigorous growth and abundant flowering during the active growing season. A balanced liquid fertilizer, diluted to half strength, can be applied every two to four weeks. As plants begin to bloom, switching to a fertilizer higher in potassium can encourage continuous flowering. Avoid over-fertilizing, as this can lead to excessive leafy growth at the expense of blooms and may cause salt buildup in the soil.
Propagation Methods
Propagating Pelargoniums from stem cuttings is a reliable method to create new plants. Select healthy, non-flowering stems, ideally in late summer or early autumn, as they root effectively during active growth. Make a clean cut just below a leaf node, removing any lower leaves and flower buds from the bottom two-thirds of the cutting. This exposes the area where roots are most likely to form.
Allow the cuttings to air-dry for a few hours to form a callus at the cut end, which helps prevent rot. Insert the prepared cuttings into a well-draining potting mix, such as a blend of compost and grit or sand. While rooting hormone can be used to encourage root development, it is often not strictly necessary as Pelargoniums root readily. Place the potted cuttings in a warm location with bright, indirect light, keeping the soil lightly moist but not saturated. Roots typically form within two to three weeks, at which point new growth indicates successful establishment.
Common Problems
Pelargoniums can encounter several common issues, including pests and care-related concerns. Aphids, whiteflies, and spider mites are frequent insect pests that can infest foliage, potentially causing distortion or discoloration. Inspecting plants regularly and using insecticidal soap can help manage these infestations.
Overwatering is a common cause of problems, leading to root rot, characterized by wilting and yellowing lower leaves. Ensuring proper drainage and allowing the soil to dry between waterings can prevent this. Yellowing leaves can also signal nutrient deficiencies, particularly nitrogen, insufficient light, or underwatering, often along leaf edges. Fungal diseases, such as rust, may appear as brown spots on leaves, especially in damp conditions, and affected leaves should be removed. Lack of blooms can be attributed to insufficient light or over-fertilization with too much nitrogen.