Overview
Dryopteris dilatata, also known as broad buckler-fern, is a species of fern that belongs to the family Dryopteridaceae, native to Europe and parts of Asia and North America. It is a tall, hardy species that thrives in humid conditions, and is often used for ornamental purposes or medicinal remedies.
Common Names
Dryopteris dilatata is commonly known as broad buckler-fern, male fern, and shield fern. These names are derived from the plant's shield-shaped foliage and its reproductive organs that resemble miniature shields.
Appearance
The foliage of Dryopteris dilatata is typically between 50-120 cm tall, with large, green, triangular leaves that taper towards the base. The leaves are arranged in a symmetrical manner around a central stalk, and are divided into several pointed segments. The plant's reproductive organs are found on the underside of the leaves, in the form of spores that are arranged in small clusters or sori. These sori are covered by a thin, protective layer known as an indusium, and are only visible on closer inspection.
Uses
Dryopteris dilatata is commonly used for ornamental purposes, often potted and used in indoor gardens or as a decorative addition to outdoor landscapes. It is also sometimes used for medicinal remedies, with the plant's extract being used to treat issues such as kidney and bladder problems, menstrual cramps, and skin irritations. Additionally, the plant's leaves can be dried and used as a natural bug repellent, with the oil extracted from the leaves being effective at repelling insects like mosquitos.
Light Requirements
Dryopteris dilatata requires a moderate level of indirect light. Direct exposure to the sun can scorch the leaves and stunt the plant's growth. Therefore, it thrives best in partially shaded areas or under the canopy of larger trees that can offer partial shading.
Temperature Requirements
Temperature is a significant factor affecting the growth and development of Dryopteris dilatata. The typical temperature range at which the plant grows is between 15°C to 22°C (59°F to 72°F). It prefers a cool and humid environment that mimics the understory of a deciduous forest. Frost and extreme heat can damage or kill the plant, so it is vital to ensure the temperature stays within the ideal range.
Soil Requirements
The growth and development of Dryopteris dilatata significantly depend on the quality and type of soil. It thrives best in a well-draining, loamy soil that is moderately moist. The soil pH should be between 5.5 and 7.5. The plant requires moderate amounts of nutrients to grow, but the soil should not be too nutrient-rich, as the plant can be sensitive to excessive amounts of nitrogen or phosphorus. A light application of organic matter or fertilizer once per year can promote its growth and development.
Cultivation Methods
Dryopteris dilatata (Hoffmann) Gray ssp. americana (Fisch.) Hultén, also known as the American shield fern, is a hardy plant that can tolerate a wide range of growing conditions. It is commonly grown in shaded areas of gardens, rock gardens, naturalized areas, and woodland gardens. The plant prefers well-drained soils that are rich in organic matter and have a pH range of 5.5 to 7.0.
When planting, ensure that the soil is loosened to a depth of at least 6 inches and amended with compost or well-rotted manure. The plant should be placed in a hole that is twice as wide as the root ball and at the same level as it was previously growing.
Watering Needs
American shield ferns require consistent moisture to thrive, but not too much water as it can lead to fungal diseases and root rot. Water the plant deeply once or twice a week during dry weather, ensuring that the water reaches the roots. Avoid watering the leaves as it can lead to fungal infections. Mulching can help to retain moisture in the soil and prevent evaporation.
Fertilization
Dryopteris dilatata (Hoffmann) Gray ssp. americana (Fisch.) Hultén plants do not require regular fertilization, but they benefit from an annual application of organic fertilizer in the spring. Use a granular or slow-release fertilizer that is low in nitrogen and high in phosphorus and potassium. Avoid applying fertilizer too close to the plant's base.
Pruning
American shield ferns require very little pruning, but removing dead or damaged fronds can help to maintain the plant's appearance and health. Pruning should be done in the late winter or early spring before new growth appears. Cut back the fronds to the base of the plant using sharp, sanitized pruning shears. You can also divide the plant every few years in the early spring to maintain its vigor and spread.
Propagation of Dryopteris dilatata ssp. americana
Dryopteris dilatata ssp. americana, commonly known as American shield fern, is a native fern species in North America. Propagation of this fern species can be done through spores or division of rhizomes.
Propagation through spores
Propagation through spores is a popular method of propagating fern species, including Dryopteris dilatata ssp. americana. To propagate through spores, collect mature sori (clusters of spores) from the underside of the fronds. Mature sori are usually brown or black in color. Place the sori in a flat container with damp sphagnum moss and cover with plastic wrap. Keep the container in a warm and bright location with indirect sunlight. Check the container regularly to ensure the moss remains damp. Once the spores germinate, small ferns will appear. Transplant the small ferns to individual pots or to the desired location in the garden.
Propagation through division of rhizomes
Propagation through division of rhizomes is another successful method of propagating Dryopteris dilatata ssp. americana. Rhizomes are modified stems that grow underground and produce roots and shoots. To propagate through division of rhizomes, carefully dig up the fern plant, or a mature rhizome of the plant, and separate it into smaller sections. Ensure that each section has healthy roots and shoots. Plant each section in an appropriate location with well-draining soil and partial shade. Be sure to water the newly planted sections regularly until they become established in their new location.
Disease and Pest Management for Dryopteris Dilatata (Hoffmann) Gray ssp. Americana (Fisch.) Hultén
Dryopteris dilatata (Hoffmann) Gray ssp. americana (Fisch.) Hultén, commonly known as the spreading wood fern, is a deciduous fern that is native to North America. While this plant is fairly hardy and disease-resistant, it can still fall victim to a few common diseases and pests.
Diseases
One of the most common diseases that can impact Dryopteris dilatata is leaf spot. This fungal disease appears as small, circular spots on the leaf that can be brown or black in color. The best way to prevent leaf spot is to ensure the plant is not overcrowded and receives plenty of air circulation. If you notice signs of leaf spot, remove the affected leaves and destroy them to prevent the spread of the disease.
Another disease that can affect Dryopteris dilatata is rust. This fungal disease appears as small, orange or yellow spots on the undersides of leaves. As with leaf spot, prevention is the best strategy for managing rust. Make sure the plant has ample space and air circulation, and remove any infected leaves as soon as possible.
Pests
One common pest that can impact Dryopteris dilatata is the Japanese beetle. These insects are especially attracted to the foliage of this fern and can quickly devour the leaves. If you notice signs of Japanese beetles, such as holes in the leaves, you can handpick them off the plant and drop them in a bucket of soapy water to dispose of them. Alternatively, you can use a pesticide that targets Japanese beetles, although this should be a last resort.
Another common pest that can impact Dryopteris dilatata is the slug. Slugs are especially drawn to the moist areas around the base of the plant. You can deter slugs by removing any debris or vegetation around the plant that might provide a habitat, and by keeping the surrounding area clean and dry. Slug baits can also be effective, although they should be used sparingly and with caution.
