Overview
Cotula sericea L.f. is a flowering plant that belongs to the Asteraceae family and is native to South Africa. It is a low-growing, herbaceous perennial that has several uses and common names.
Description
Cotula sericea has a mat-forming growth habit and typically reaches a height of only 5 to 10 cm. It spreads by trailing stems and forms dense clumps of finely-divided, silver-gray leaves that are silky to the touch and emit a pungent fragrance when crushed. The flowerheads, which appear in late spring and summer, are yellow, button-like discs surrounded by papery white bracts and are carried on slender stems that rise slightly above the foliage.
Common Names
Cotula sericea is commonly known as Silver Cotula, Silverweed, and Cape Weed.
Uses
Cotula sericea has several uses and is grown as an ornamental plant in many gardens. It is drought-tolerant and can be grown in rock gardens, containers, or as a ground cover. In traditional medicine, the leaves and stems of Cotula sericea have been used to treat various ailments such as colds, flu, and stomach pains. It is also used in the cosmetic industry for its fragrant oil.
Light Requirements
Cotula sericea L.f. plants require full to partial sunlight to grow and thrive. They cannot tolerate full shade and need a minimum of 6 hours of direct sunlight daily. Excessive exposure to direct sunlight during extreme summer may lead to sunburn and damage to the plant. Therefore, it's advisable to provide some shade during hot summer days.
Temperature Requirements
The ideal temperature for Cotula sericea L.f. plants ranges from 18°C to 22°C. These plants cannot tolerate frost and extreme hot conditions. During the winter season, it's advisable to move the plant indoors to protect it from frost. During the summer season, providing shade and adequate watering can help the plant maintain the required temperature.
Soil Requirements
Cotula sericea L.f. plants prefer slightly acidic to neutral soil conditions. The soil should be well-draining and rich in organic matter. These plants can grow in a wide range of soils, including sandy, loamy, and clay soils. However, the soil should not be water-logged, as it may lead to root rot.
It's advisable to prepare the soil by adding a generous amount of compost and manure to improve soil fertility and structure. For potted plants, a well-draining potting mix is ideal.
Cultivation methods
The Cotula sericea L.f. plant is a low-growing perennial that is typically grown in full sun or partial shade. It prefers well-drained soil and can tolerate a wide range of soil types, including sandy, loamy, or rocky soil. The plant can be propagated by division, root cuttings, or by seed.
If starting from seeds, sow them in a well-draining potting mix, covering them lightly with soil. Keep the soil moist but not too wet until the seedlings emerge.
When planting outdoors, space the plants 6 to 12 inches apart and water them well after planting. Mulching around the plants can help keep the soil moist and prevent weeds from growing.
Watering needs
Cotula sericea L.f. prefers to be kept moist but not waterlogged. Water the plant deeply once a week, or more often during particularly hot or dry weather. Allow the soil to dry out slightly between watering to prevent overwatering, which can lead to root rot.
Do not water the plant from above, as wet foliage can encourage fungal diseases. Instead, water the soil around the plant, making sure to reach all the way to the root system.
Fertilization
Cotula sericea L.f. does not require heavy fertilization. A light application of a balanced, slow-release fertilizer in the spring can provide the plant with the necessary nutrients for the growing season. Be careful not to overfertilize, which can lead to excessive foliage growth at the expense of flowering.
Pruning
When it comes to pruning, Cotula sericea L.f. benefits from a light trim in late summer or early fall. This helps to keep the plant compact and encourages bushier growth. Remove any dead or damaged stems as needed, but avoid cutting back too much of the plant at once.
Deadheading spent flowers throughout the growing season can help to encourage prolonged blooming.
Propagation of Cotula sericea L.f.
Cotula sericea L.f. can be propagated using various methods depending on the type of growth of the plant. Some of the propagation methods include:
Seed Propagation
The most common and easiest way of propagating Cotula sericea L.f. is through seed propagation. The seeds can be collected during the flowering season and can be sown in a nursery bed or directly in the field. The seeds should be sown at a depth of about 1-2 cm and spaced at 5-10 cm apart. The soil should be kept moist and the seeds should germinate within 10-20 days. Once the seedlings have grown to a suitable size, they can be transplanted to their final location.
Cutting Propagation
Cuttings can also be used to propagate Cotula sericea L.f. For this method, choose healthy stems from the parent plant, making sure they are free of disease and pests. The cuttings should be taken during the growing season and kept in a moist environment to prevent drying out. The cuttings should be planted in well-draining soil and kept moist until they have rooted. This method of propagation is best done in the warmer months when the plant is actively growing.
Division Propagation
Division propagation can also be used for Cotula sericea L.f. This method involves dividing the parent plant into smaller sections with a sharp cutting tool. Each division should contain both roots and shoots. The divisions can then be planted in separate locations and should be watered regularly until they become established.
Overall, Cotula sericea L.f. can be propagated using a variety of methods. Seed propagation is the easiest and most common method, but cutting and division propagation can also be used successfully.
Disease and Pest Management of Cotula sericea L.f.
Cotula sericea L.f. is known to be a hardy and low maintenance plant. However, like any other plant, this species is also prone to pests and diseases that may affect its growth and overall health. Here are some common diseases and pests that might affect the plant and ways to manage them:
Pests
Cutworms: Cutworms are known to feed on the plant’s stems at the soil line, causing it to wilt and eventually die. Crop rotation can help in the management of cutworms. Remove weeds and other debris that can serve as their hiding place. Handpicking the worms and keeping the soil free from weeds can also limit the infestation. Insecticides can also be used as a last resort.
Aphids: Aphids suck the sap of the plants and can cause severe damage to Cotula sericea L.f. To manage this pest, regular inspection of the plant and spraying of water using a high-pressure nozzle can remove the aphids. Alternatively, insecticidal soaps can be used as these are less harmful to the plant compared to chemical insecticides. Ladybugs can also serve as a natural predator of aphids, so consider releasing them into your garden for long-term management.
Slugs and snails: Slugs and snails feed on the plant’s leaves and cause damage, leading to plant death. Trap them using beer baits or handpick them in the early mornings or late evenings. Copper strips around the plant can discourage slugs and snails from feeding. Diatomaceous earth can also be sprinkled in a ring around the plant as another option.
Diseases
Root rot: Root rot in Cotula sericea L.f. is caused by a fungal infection. It can be controlled by ensuring proper drainage of soil to avoid waterlogging. Soil sterilization using hot water or fungicides can also help in managing root rot. Discarding the infected plants and avoiding overwatering is also recommended.
Leaf spot: Leaf spots are caused by various fungi and bacteria that attack the plant’s foliage, leading to leaf drop. Maintaining proper air circulation by pruning any crowded plant parts and avoiding overhead irrigation can help manage leaf spot. Fungicides can also be used to control the spread of the disease.
In summary, regularly inspecting Cotula sericea L.f. for any signs of pests or diseases is highly recommended. Early detection and appropriate management of these issues can help prevent further damage and ensure the plant’s health and survival.
