Overview
Erucastrum meruense Jonsell subsp. meruense is a perennial plant species that belongs to the family Brassicaceae. It is commonly known as the Meru rocket or the Hoary rock-rocket and is native to East Africa, specifically Kenya and Tanzania.
Appearance
The Meru rocket plant typically grows up to a height of 30-45 cm and produces a cluster of small white flowers at the top of the stem. It has a narrow and elongated stem that is covered with fine hairs, giving it a hoary appearance and enhancing its ability to weather windy conditions. The leaves of the Meru rocket plant are simple, toothed, and elongated, with a blue-green coloration that contrasts with its white flowers.
Uses
The Meru rocket plant is used primarily for medicinal purposes in traditional African medicine. The plant's leaves are crushed and applied to wounds and bruises, as well as to reduce fever and treat respiratory infections. Additionally, the seeds of the Meru rocket plant are edible, and are used as a source of food and oil for indigenous African communities.
In summary, Erucastrum meruense Jonsell subsp. meruense, also known as the Meru rocket or the Hoary rock-rocket, is a perennial plant species that is indigenous to East Africa. It is identifiable by its narrow and elongated stem, toothed leaves, and small white flowers. The plant is primarily used for medicinal purposes and its seeds are a source of food and oil.Light Requirements
Erucastrum meruense Jonsell subsp. meruense requires full sunlight or partial shade to grow properly. This plant cannot survive in complete shade.
Temperature preferences
Erucastrum meruense Jonsell subsp. meruense prefers to grow in temperatures ranging from 5-25°C. This plant can grow in colder temperatures as well but it does not tolerate frost. Therefore, it is essential to protect the plant during frosty conditions.
Soil Conditions
This plant can grow in different types of soils such as sandy, loamy or clayey soils. However, it prefers well-draining soils with a pH range from 5.5 to 7.5. Adequate moisture should be maintained in the soil to sustain proper growth.
Cultivation Methods
Erucastrum meruense Jonsell subsp. meruense is an herbaceous plant that requires well-draining soils with a pH of 6.5 to 7.5. It thrives in areas with temperatures ranging from 15 to 25 degrees Celsius and requires full sunlight for optimal growth. The plant has a tap root system that enables it to extract water and nutrients from deep soils.
Watering Needs
The plant requires moderate watering to thrive; a dry spell of up to three weeks does not affect the plant's growth significantly. Overwatering the plant may lead to rotting of the roots or the development of fungal and bacterial infections. For best results, drip irrigation is recommended, as it provides the plant's roots with a gradual and consistent supply of moisture.
Fertilization
Proper fertilization is crucial for Erucastrum meruense Jonsell subsp. meruense to thrive. The plant requires a balanced supply of fertilizers, including nitrogen, potassium, and phosphorus, which are essential in promoting plant growth and development. Organic fertilizers such as compost manure are highly recommended as they improve soil fertility and soil structure.
Pruning
Pruning is not necessary for Erucastrum meruense Jonsell subsp. meruense as it rarely develops any undesired growth. However, trimming the mature plants to half their initial size after flowering is complete may promote the development of new foliage and flowers later in the season. The plant does not require any stake support as its stems are sturdy enough to support the plant's growth throughout its lifespan.
Propagation of Erucastrum meruense Jonsell subsp. meruense
Erucastrum meruense Jonsell subsp. meruense is propagated both by seeds and vegetatively.
Propagation by Seeds
The plant produces small seeds that can be sown in pots or trays indoors or directly in the ground outdoors. The best time to sow the seeds is in late spring or early summer. The seeds should be planted in well-drained soil that is rich in organic matter. They should be sown in shallow trenches and covered lightly with soil.
Once the seeds have germinated, they need to be thinned out to around 10 – 15 cm apart to give them enough room to grow. The young seedlings should be watered frequently, and the soil should be kept moist but not waterlogged.
After around four to six weeks, the seedlings should be strong enough to be transplanted into their final growing position.
Propagation by Vegetative Means
Erucastrum meruense Jonsell subsp. meruense can also be propagated vegetatively through stem cuttings. This is usually done in late spring or early summer when the plant is actively growing.
Cut off a 10 – 15 cm long stem from the plant. Remove the leaves from the bottom half of the stem, leaving the top leaves intact. Dip the bottom end of the stem in rooting hormone, and plant it in well-drained soil. The soil should be kept moist but not waterlogged.
The cutting should be placed in a bright location but out of direct sunlight to avoid scorching the leaves. Roots will develop in around four to six weeks, and the plant can be transplanted into its final growing position.
Disease Management
Erucastrum meruense Jonsell subsp. meruense is generally a hardy plant and not particularly susceptible to diseases, but it can be affected by:
Anthracnose
Anthracnose is a fungal disease that causes dark, sunken spots on the leaves and stems. To manage anthracnose, it is important to remove and destroy any affected plants or plant parts, and to prevent the disease from spreading by ensuring adequate spacing between plants and providing good air circulation.
Downy Mildew
Downy mildew is a fungal disease that causes yellowing and wilting of leaves. Use of resistant varieties is the most effective management strategy against this disease. You can also remove and destroy infected foliage and soil in order to prevent spread. Ensure good air circulation at the plant base watering early in the morning to minimize the time foliage is wet.
Pest Management
The common pests that can affect Erucastrum meruense subsp. meruense are:
Aphids
Aphids are small insects that feed on the sap of plants, causing stunted growth, yellowing of leaves, and wilting. To manage aphids, you can blast them off the plant with a strong spray of water or remove them by hand. You can also release natural predators such as ladybugs or lacewings in your garden to help control the aphid populations.
Cutworms
Cutworms are caterpillars that cut the stems of young plants. To manage cutworms, you can place a collar made of cardboard or aluminum foil around the base of the plant, or plant seedlings in small pots with their bottoms removed and buried in the soil to a depth of one inch, keeping the collar about one inch above the soil. This will make it more difficult for cutworms to access the plants.
Slugs
Slugs are soft-bodied, shell-less mollusks that can eat holes in leaves and leave slimy trails behind. To manage slugs, you can handpick them at night when they are most active, or use slug pellets or traps. Alternately, you can encourage natural predators of slugs such as birds, toads, and snakes to frequent your garden.
