Origin
Plectranthus purpuratus Harv. subsp. purpuratus, commonly known as purple spurflower, is a perennial plant species native to South Africa. It belongs to the Lamiaceae family and is closely related to other widely cultivated ornamental plants like coleus and mint.Common Names
Apart from purple spurflower, Plectranthus purpuratus Harv. subsp. purpuratus is known by several other names in different regions. Some of the common names for this plant include Vick's plant, mint-leaved spurflower, and large spurflower.Uses
Plectranthus purpuratus Harv. subsp. purpuratus is popular for its ornamental value. Due to its attractive foliage and beautiful lavender-blue flowers, this plant is commonly grown as an ornamental plant in gardens, parks, and as a houseplant. Moreover, this plant possesses a pleasant aroma, similar to that of menthol. This makes Plectranthus purpuratus Harv. subsp. purpuratus suitable for indoor plant cultivation, where its fragrance can purify indoor air and create a pleasant ambiance.General Appearance
Plectranthus purpuratus Harv. subsp. purpuratus is a medium-sized plant that can grow up to 3 feet tall and 2 feet wide. The plant has soft-textured, purple-green leaves that are ovate, slightly serrated and up to 2 inches long. The plant's inflorescence consists of spikes of flowers that follow the stem's growth. These flowers are lavender-blue, tubular, and two-lipped, with darker purple markings on the underside of the tubes. When the plant blooms, the flowers form a dense spike that resembles a candle. Overall, the plant is very attractive, and its deep green and purple leaves, combined with its bright flowers, provide an excellent addition to gardens or indoor spaces.Light Requirements
Plectranthus purpuratus Harv. subsp. purpuratus typically thrives in bright, but indirect sunlight. It is crucial to avoid placing the plant in direct sunlight as it may scorch its leaves. This plant grows well in low light conditions too, but the leaves will be slightly smaller.
Temperature Requirements
The plant grows well in warm temperatures ranging from 60°F to 85°F. It cannot withstand frosts or freezing temperatures. Plectranthus purpuratus Harv. subsp. purpuratus should be kept at temperatures above 40°F to avoid its leaves from being damaged by cold weather.
Soil Requirements
This plant grows well in well-draining soil that is moist but not water-logged. The ideal soil mixture should have equal parts perlite, peat moss, and coarse sand. The PH of the soil should be maintained between 6.0 and 7.5. Fertilize the plant every two weeks with a water-soluble fertilizer during the growing season. It is recommended to re-pot the plant every 2-3 years to prevent its roots from becoming root-bound.
Cultivation Methods
Plectranthus purpuratus is an easy-to-grow plant that can thrive both indoors and outdoors. It prefers well-draining, sandy soil and moderate temperatures. For indoor cultivation, it is best to place it near a window that receives indirect sunlight. Outdoor plants should be placed in an area that receives morning sun and partial shade in the afternoon.
Propagation can be carried out through cuttings or seedlings. Cuttings can be taken from the plant during the growing season and planted in moist potting soil. Seedlings can be sown in the early spring and transplanted once they have reached a height of 3-4 inches.
Watering Needs
Plectranthus purpuratus requires moderate watering. Overwatering should be avoided as it can lead to root rot. Water the plant thoroughly and then allow the soil to dry out partially before watering again. During the winter season, reduce watering as the plant goes into a dormant phase.
Fertilization
Regular fertilization can lead to healthy growth and increase the plant's resistance to disease and pests. Fertilize once in two weeks with a balanced, water-soluble fertilizer during the growing season. During the winter season, fertilization should be limited to once every four weeks. Use fertilizers with a higher potassium content during the winter season to encourage flowering.
Pruning
Pruning Plectranthus purpuratus is essential to maintain a healthy and aesthetically pleasing plant. It can be pruned at any time during the growing season to control the plant's size and shape. Deadheading the flowers can promote more blooms.
The plant can be pruned back severely before the winter season to encourage fresh growth in the spring. Also, remove any dead or diseased plant material immediately to prevent the spread of disease.
Propagation of Plectranthus purpuratus Harv. subsp. purpuratus:
Propagation of Plectranthus purpuratus can be achieved through various methods including seeds, cuttings, and division.
Propagation by Seeds:
Propagation by seeds is possible but can be a bit challenging. Collect seeds from mature and healthy plants. Sow the seeds in a pot filled with well-draining soil mix. Keep the soil moist and warm (between 65-75°F) for good germination. Germination takes two to four weeks. Seedlings can be transplanted to larger containers after they have developed at least two sets of true leaves.
Propagation by Cuttings:
Cuttings are the easiest way to propagate Plectranthus purpuratus. Take stem cuttings from non-flowering shoots. Cut a three to the five-inch section of the stem right below a node. Remove the lower leaves from the cutting and dip the cut end into a rooting hormone. Plant the cutting in a container filled with well-draining soil mix. Keep the soil moist and warm (between 65-75°F) until the root system develops. After a month, the cutting should have an established root system and be ready for transplantation to a larger container.
Propagation by Division:
Propagation by division involves separating a mature plant into smaller sections. Dig up the plant carefully and divide the root ball into smaller sections. Replant the smaller sections in individual containers or in the ground with a well-draining soil mix and keep the soil moist until the plants become established. This method works well for mature plants with multiple stems.
Disease and Pest Management for Plectranthus purpuratus Harv. subsp. purpuratus
Plectranthus purpuratus Harv. subsp. purpuratus is generally a healthy plant that can resist most pests and diseases. However, certain environmental factors such as excessive moisture or poor soil drainage can make the plant vulnerable to diseases and pests. In such cases, it is important to take prompt action to prevent the spread of the menace and save the plant.
Common Diseases that Affect Plectranthus purpuratus Harv. subsp. purpuratus
The following are some common diseases that are known to affect Plectranthus purpuratus Harv. subsp. purpuratus:
1. Root Rot
Root rot is a fungal disease caused by overwatering or poor soil drainage. Symptoms of root rot include wilting, yellowing, and eventual death of the plant. To prevent root rot, ensure the soil has proper drainage, avoid overwatering, and remove infected plants to prevent the spread of the fungus.
2. Powdery Mildew
Powdery mildew is a fungal disease that affects many plants, including Plectranthus purpuratus. It is characterized by a white powdery substance on the leaves and stem. To prevent powdery mildew, maintain proper air circulation around the plant, avoid over-fertilization, and remove affected leaves immediately.
Common Pests that Affect Plectranthus purpuratus Harv. subsp. purpuratus
The following are some common pests that are known to affect Plectranthus purpuratus Harv. subsp. purpuratus:
1. Mealybugs
Mealybugs are small, soft-bodied insects that suck sap from plants, causing stunted growth and yellowing of leaves. Remove mealybugs manually with a cotton swab dipped in rubbing alcohol or insecticidal soap to control their populations.
2. Spider Mites
Spider mites are also sap-sucking pests that can cause yellowing and wilting of leaves. They are identified by their webbing on the undersides of leaves. To get rid of spider mites, remove heavily infested leaves, increase humidity around the plant, and use insecticidal soap or pesticide spray.
Regular monitoring, maintaining proper plant hygiene, and providing ideal growing conditions are essential to prevent common diseases and pests from affecting Plectranthus purpuratus Harv. subsp. purpuratus. Follow the above measures to ensure that your plant remains healthy and productive all year round.
