Origin and Common Names
Myrcia citrifolia (Aubl.) Urban var. imrayana (Griseb.) Stehlé & Quentin, commonly known as guayabilla or redberry stopper, is a small tree or shrub that belongs to the Myrtaceae family. It is native to the Caribbean islands, including Puerto Rico and the Lesser Antilles. The plant is also found in South America, particularly in Colombia, Venezuela, and Brazil.Uses
The guayabilla fruit is edible and is mainly consumed fresh or made into jams and jellies. The leaves of the Myrcia citrifolia are used to make an infusion that is believed to have medicinal properties, such as treating respiratory infections, fever, and digestive issues. The plant is also valued for its ornamental purposes, as it produces beautiful white flowers and red-brownish fruits.General Appearance
The Myrcia citrifolia shrub can grow up to 8 meters in height and has a dense, bushy crown. The leaves are 3 to 8 cm in length and are thick, smooth, and shiny, with a bright green color. The tree produces small, white flowers that are approximately 1 cm in diameter with four or five petals. The fruit is small, oval-shaped, and measures about 1 cm in length. When ripe, the fruit turns a bright red color and has a sweet, slightly tangy taste. The plant prefers moist, well-drained soil and is typically found in shady areas of forests, on the banks of rivers, and in coastal areas.Light Requirements
The Myrcia citrifolia var. imrayana plant prefers full sun exposure for optimal growth. It requires at least 6 hours of direct sunlight every day. The plant can tolerate partial shade, but it may affect the quality and quantity of fruit production.
Temperature Requirements
The Myrcia citrifolia var. imrayana plant requires a warm and humid climate for optimal growth. The plant can thrive in temperatures ranging from 20 °C to 30 °C. Temperatures below 15 °C can damage the plant and affect its overall growth and ability to produce fruit.
Soil Requirements
The Myrcia citrifolia var. imrayana plant requires well-draining soil that is rich in organic matter. The soil pH should be slightly acidic, preferably between 5.5 and 6.5. The plant can grow in a variety of soil types, including sandy, loamy, and clay soils, as long as they are well-draining. The plant requires regular irrigation, but it cannot tolerate waterlogged soil, as this can lead to root rot and other diseases.
Cultivation methods
The Myrcia citrifolia plant is native to tropical areas and can be grown in USDA Hardiness Zones 10 and above. It prefers full sunlight and well-draining soil that is rich in organic matter. The plant can either be grown from seeds or propagated through stem cuttings, and it requires a warm and humid environment to germinate and grow. It can be planted in pots or in the ground, but it should be protected from strong winds and cold temperatures.
Watering needs
The Myrcia citrifolia plant requires regular watering, especially during the growing season. It prefers moist soil, but it should not be overwatered as this can lead to root rot. The frequency of watering depends on the humidity and temperature of the environment. During the dry season, the plant may require more frequent watering to prevent the soil from drying out.
Fertilization
Fertilization is important for the Myrcia citrifolia plant to encourage healthy growth and fruit production. A balanced fertilizer with a ratio of 10-10-10 or 20-20-20 can be applied every three months during the growing season. Organic fertilizers such as compost or manure can also be used, but they should be applied sparingly to avoid root burn.
Pruning
Pruning is not necessary for the Myrcia citrifolia plant to produce fruit, but it can help to shape the plant and remove any dead or diseased branches. Pruning should be done during the dormant season, and any pruning cuts should be made just above a healthy bud. The plant can also be pinched back to encourage bushier growth and more fruit production.
Propagation of Myrcia citrifolia var. imrayana
Myrcia citrifolia var. imrayana is commonly propagated through seeds, cuttings, and grafting.
Seed Propagation
Seeds are collected from ripe fruits and sowed immediately in sterilized soil. The seeds require warm temperatures and high humidity for germination. The soil needs to be moist but not waterlogged. Germination usually takes around 1-2 months.
Cutting Propagation
Cuttings are taken from healthy, mature plants. The cuttings should be around 10-15 cm long and taken during the plant's dormant season. Treat the cutting with rooting hormone and plant in a well-draining soil mix. The soil should be kept moist but not saturated. The cuttings will develop new roots in 4-8 weeks.
Grafting Propagation
Grafting can be used to propagate Myrcia citrifolia var. imrayana onto a rootstock of a related species. This method is commonly used to maintain desirable characteristics in the plant. The process involves cutting a piece of the desired plant, called the scion, and attaching it to a part of the rootstock. It is important to ensure that the scion and rootstock's cambium layers match to allow for proper healing.
Disease Management
Myrcia citrifolia, commonly known as Guava Cimarron, is susceptible to various types of fungal diseases, such as anthracnose, powdery mildew, and rust. Proper sanitation practices and preventive measures should be employed to manage these diseases.
Anthracnose can be managed by pruning infected leaves and shoots, removing and disposing of fallen leaves, and avoiding overhead irrigation. The application of copper fungicides can also be effective.
Powdery mildew can be prevented by ensuring good air circulation, avoiding overhead irrigation, and managing humidity levels. Fungicides containing trifloxystrobin, azoxystrobin, or sulfur can also be used.
Rust can be managed by pruning infected leaves and shoots, removing and disposing of fallen leaves, and using preventive fungicide sprays.
Pest Management
Guava Cimarron can also be attacked by a variety of pests, such as the Caribbean fruit fly, the Anastrepha suspensa, scale insects, and whiteflies. Proper management strategies should be implemented to prevent and control these pests.
Preventive measures, such as removing damaged or fallen fruit, can be used to control Caribbean fruit flies. The application of insecticides, such as malathion or spinosad, can also be effective.
Scale insects can be managed by pruning affected parts of the plant and using insecticidal soaps or horticultural oils.
Whiteflies can be managed by using insecticidal soaps or oils, or by introducing natural predators such as ladybugs or lacewings. Yellow sticky traps can also be effective in trapping whiteflies.
