Overview:
Pelargonium laevigatum (L.f.) Willd. subsp. laevigatum, commonly known as the smooth-leaved scented geranium, is an evergreen shrub that belongs to the Geraniaceae family. This species is native to South Africa, where it can be found growing wild in the Western Cape region.
Appearance:
The smooth-leaved scented geranium is a perennial plant that can reach a height of up to 1.5 meters. It has semi-woody stems that are covered with a smooth, greyish bark. The leaves are ovate in shape and have a glossy, dark green color. The margins of the leaves are toothed and slightly undulated. The plant produces small, pink to lavender-colored flowers that are arranged in clusters.
Common Names:
The smooth-leaved scented geranium is known by various names, including the following:
- Smooth Pelargonium
- Smooth-leaved Scented Geranium
- Smooth-leaved Geranium
Uses:
The smooth-leaved scented geranium is popular for its pleasing aroma. The leaves of the plant emit a sweet, floral scent that is commonly used in perfumes and other fragrances. The plant is also used in culinary applications, where it is utilized to flavor teas, desserts, and other sweet dishes. In addition, the smooth-leaved scented geranium is believed to possess medicinal properties. The plant has been used in traditional medicine to treat various ailments, including stomach disorders, respiratory issues, and skin irritations.
Light Requirements
Pelargonium laevigatum subsp. laevigatum thrives in full sunlight. It requires at least six hours of direct sunlight a day. However, it can also tolerate light shade during the hottest parts of the day. Too much shade can lead to legginess and reduced flower production.
Temperature Requirements
For optimal growth, Pelargonium laevigatum subsp. laevigatum prefers moderate temperatures ranging from 20 to 25°C during the day. It can tolerate a minimum of 5°C at night, but temperatures below this might damage or kill the plant. In regions with higher temperatures, it's recommended to plant the Pelargonium in areas where it can benefit from partial shade.
Soil Requirements
Pelargonium laevigatum subsp. laevigatum prefers well-draining soil that's rich in organic matter. The soil should have a pH range of 6-7.5. It can grow in many soil types, but it doesn't do well in heavy clay soils that retain water for long periods. Before planting, it is recommended to amend the soil with compost or aged manure to improve fertility and drainage.
Cultivation Methods
Pelargonium laevigatum (L.f.) Willd. subsp. laevigatum belongs to the family Geraniaceae and is native to South Africa. The plant can grow up to a height of 2 meters. The best time to plant this species is in early spring. The ideal soil type is well-drained with a pH range of 6.0-7.0. It prefers full sun and can tolerate partial shade.
Watering Needs
Pelargonium laevigatum requires moderate watering. It prefers to be kept moderately dry and does not tolerate water-logged soils. The soil should be allowed to dry out between watering, and care should be taken not to overwater the plant. During the growing season, the plant needs frequent watering, typically 2-3 times a week.
Fertilization
Pelargonium laevigatum requires a balanced fertilizer application every 2-3 weeks during the growing season, from spring to fall. Avoid fertilizing during winter when the plant is dormant. Use a low-nitrogen fertilizer as a high concentration of nitrogen can lead to excessive foliage growth at the expense of flowers.
Pruning
Pelargonium laevigatum, like most pelargoniums, benefits from regular pruning. Pruning is done to shape the plant, remove dead or damaged leaves and to encourage growth and flowering. Pruning should be done in early spring, just before new growth begins. Pinch back the stems to encourage branching and bushiness. Prune away any dead or decaying leaves and stems as soon as they appear.
Propagation of Pelargonium laevigatum subsp. laevigatum
Pelargonium laevigatum subsp. laevigatum can be propagated by various methods, including seeds, cuttings, and division.
Seed Propagation
The easiest and most common method of propagating Pelargonium laevigatum subsp. laevigatum is by seeds. Collect the seed capsules once they have dried out on the plant. Sow the seeds in a well-drained, sandy, or gritty soil mixture. Keep the soil consistently moist but not soggy and maintain a temperature of 68-77°F (20-25°C). Seeds usually germinate within two weeks to a month time. Once the seedlings have reached approximately 2 inches tall, they can be transplanted to larger pots or containers with fertile, well-draining soil mixture.
Cutting Propagation
Pelargonium laevigatum subsp. laevigatum can also be propagated from stem cuttings. Select healthy, green stems that do not have any flowers or flower buds. Cut a 4-6 inch piece of stem, remove the leaves from the bottom 2 inches, and dip the cut end in rooting hormone. Place the cutting in a well-drained soil mixture. Keep the soil moist and cover the pot or tray with plastic or a clear lid to keep humidity levels high. After 3-4 weeks, the cutting should develop roots and can be transplanted to larger pots or containers with fertile, well-draining soil mixture.
Division Propagation
Pelargonium laevigatum subsp. laevigatum can be propagated by division as well. This method is best suited for older plants that have become large and overgrown. Gently remove the plant from its pot or container and separate the root ball into smaller sections. Make sure that each section has both roots and foliage. Replant each section in its pot or container with fertile, well-draining soil mixture and water thoroughly. Keep the soil moist and place the pot or container in a shaded or partially shaded area until new growth appears.
Common Diseases and Pests for Pelargonium laevigatum (L.f.) Willd. subsp. laevigatum
Pelargonium laevigatum (L.f.) Willd. subsp. laevigatum may be susceptible to various diseases and pests. Among the common diseases are:
Crown rot diseases
Caused by Phytophthora fungi, crown rot diseases can be detrimental to the roots and base of the plant. When affected by crown rot, plants may show wilting or yellowing leaves, stunted growth, or premature death. One management solution is to avoid overhead watering and improve soil drainage to reduce soil moisture. If plants are already infected, chemical fungicides can be used, but the best approach is to remove and destroy the affected plants to prevent further spreading of the disease.
Black spot
Black spot is a fungal disease that shows circular dark spots on the leaves, often leading to their yellowing and dropping off. Good hygiene and sanitation practices such as removing fallen leaves and debris can control the spread of the disease. Chemical fungicides also help in managing black spot.
Gray mold
Gray mold is a common disease in wet and warm environments, caused by the Botrytis fungus. Infected leaves may have small, dark, water-soaked lesions. If left unmanaged, gray mold can cause decreased plant vigor and yield. To prevent the disease, avoid overhead watering and reduce humidity levels. Proper air circulation and spacing also aid in disease management. If plants are already infected, dispose of them to avoid spreading the disease.
Caterpillars
Caterpillars can consume large amounts of foliage and can cause significant damage to plants. They can be managed through cultural methods such as hand-picking and application of Bacillus thuringiensis, a bacterium that kills caterpillars. Chemical pesticides can also be effective but should be used with caution to avoid harming beneficial insects and the environment.
Aphids
Aphids are small, soft-bodied insects that can cause leaf distortion, curling, and yellowing. They suck the sap from the plant's tissues and excrete a sugary solution that often attracts ants. Non-chemical methods such as the application of insecticidal soap can help deter and control the spread of aphids. Other methods include introducing natural predators like ladybugs, lacewings, and parasitic wasps.
