Imperata, a genus of grasses, with a particular focus on Imperata cylindrica, commonly known as cogongrass, and its cultivar 'Red Baron' (also known as Japanese Blood Grass). This grass elicits strong reactions – it is both highly valued for its ornamental qualities and notorious for its extreme invasiveness in many regions.

What Makes Imperata cylindrica 'Red Baron' So Special (and Potentially Problematic)

• Stunning Red Foliage: This is the primary reason for its popularity. 'Red Baron' has striking, upright leaves that emerge green and progressively turn a brilliant, blood-red color, starting at the tips and moving downward. The color intensifies in full sun and during cooler weather. This red is exceptionally vibrant and provides a strong contrast in the landscape.
• Architectural Form: The upright, clumping growth habit adds a vertical element and textural interest to the garden.
• Seasonal Interest: The red color is most intense in summer and fall, providing a welcome splash of color when many other plants are fading.
• (The Problem) Extreme Invasiveness (Species, not 'Red Baron'): While 'Red Baron' is generally considered less invasive than the species Imperata cylindrica, this is a critical point. The straight species, cogongrass, is one of the world's worst invasive weeds. It spreads aggressively by rhizomes and seeds, forming dense stands that outcompete native vegetation. It is crucial to understand this distinction and to never plant the straight species. 'Red Baron' is thought to be less invasive because it rarely flowers and sets seed, relying primarily on rhizomatous spread. However, it can still spread aggressively under favorable conditions, and there is a risk of reversion to the green, highly invasive form.

Description and Details ('Red Baron')

• Growth Habit: Upright, clumping, perennial ornamental grass.
• Foliage: Narrow, linear leaves that emerge green and gradually turn red from the tips downward. The red color is most intense in full sun and during cooler weather.
• Flowers: Rarely flowers, especially in cooler climates. If it does flower, the inflorescences are fluffy, silvery-white plumes. These are generally considered undesirable as they can produce viable seed (increasing the risk of invasiveness).
• Fruit: Seeds (rarely produced by 'Red Baron').
• Size: Typically grows to 30-60 cm (1-2 feet) tall and wide.

Native Habitat (Imperata cylindrica - the Species)

• Origin: Native to tropical and subtropical Asia, Africa, Australia, and the Pacific Islands.
• Typical Habitats: Thrives in a wide range of habitats, including grasslands, disturbed areas, roadsides, and agricultural lands. It prefers full sun and well-drained soil but can tolerate a variety of conditions.

Landscaping Design Tips ('Red Baron' - Use with Caution!)

• Accent Plant: The striking red foliage makes it an excellent accent plant, providing a focal point in the garden.
• Mass Planting: Plant in groups or drifts for a dramatic effect.
• Mixed Borders: Combine it with other perennials and shrubs, using its red foliage to complement or contrast with other colors. Good companions include plants with yellow, blue, or purple flowers or foliage.
• Containers: It can be grown in containers, providing a vertical element and dramatic color. This is a highly recommended method of growing it, as it limits its spread.
• Modern Gardens: Its clean lines and architectural form make it a popular choice for modern and contemporary landscapes.
• Rock Gardens: It can work well in rock gardens, provided the soil is well-drained.
• Caution: Always be mindful of its potential to spread. Plant it where its spread can be easily controlled or use it in containers. Regularly monitor it and remove any unwanted runners. Never plant it near natural areas where it could escape.

Planting and Care ('Red Baron')

• Planting:
• Timing: Plant in spring or early fall.
• Spacing: Space plants 30-45 cm (12-18 inches) apart.
• Soil: Prefers well-drained soil. It can tolerate a range of soil types, including sandy, loamy, and even somewhat clay soils, as long as drainage is good.
• Light: Full sun (at least 6 hours of direct sunlight per day) is essential for the best red color. In partial shade, the color will be less intense.
• Care:
• Watering: Water regularly during the first growing season to establish a deep root system. Once established, it is relatively drought-tolerant.
• Fertilizing: Generally, it does not require much fertilization. A light application of a balanced fertilizer in spring can be beneficial.
• Pruning: Cut back the foliage to the ground in late winter or early spring before new growth emerges.
• Dividing: Divide clumps every few years in spring to rejuvenate the plant and prevent overcrowding. This is also the best way to propagate it.
• Pest and Diseases: Generally, pest and disease resistant.
• Containment: Due to its spreading nature, consider planting in containers, or using root barriers in the ground.

Taxonomy

• Kingdom: Plantae
• Phylum: Tracheophyta
• Class: Liliopsida
• Order: Poales
• Family: Poaceae (Grass family)
• Genus: Imperata
• Species: Imperata cylindrica
• Cultivar: Imperata cylindrica 'Red Baron'

Morphology

• Root System: Fibrous root system with strong, spreading rhizomes (underground stems).
• Stems (Culms): Erect, slender, and unbranched.
• Leaves: Narrow, linear, and upright, with a sharp, pointed tip. The leaves of 'Red Baron' are initially green and develop their characteristic red color.
• Flowers: (Rarely seen in 'Red Baron') Fluffy, silvery-white panicles (inflorescences).
• Fruit: Small, dry grains (caryopses) (rarely produced by 'Red Baron').

Other Insights for Gardeners

• Invasive Potential: The most crucial point to remember is the invasive potential of Imperata cylindrica. While 'Red Baron' is considered less invasive, it can still spread, and there is a risk of reversion to the highly invasive green form. Always be responsible and cautious when using this plant. Check local regulations; it may be restricted or prohibited in some areas.
• Reversion: If you notice any green shoots emerging from your 'Red Baron' plant, remove them immediately. These are reversions to the invasive species form.
• Alternatives: If you are concerned about invasiveness, consider other red-leaved grasses, such as some cultivars of Pennisetum setaceum (Fountain Grass) – but be aware that some Pennisetum species are also invasive in certain regions – or red-leaved cultivars of Miscanthus sinensis (Maiden Grass). Always research the specific plant's invasiveness in your area before planting. Panicum virgatum 'Shenandoah'(Switchgrass) offers good red color as well.
• Burning: Imperata cylindrica (the species) is highly flammable and adapted to fire. Burning can actually stimulate its growth and spread.

In conclusion, Imperata cylindrica 'Red Baron' is a stunning ornamental grass with vibrant red foliage that can add a dramatic touch to the garden. However, its potential for invasiveness (and the extreme invasiveness of the species) necessitates careful consideration and responsible planting practices. Always prioritize containment, monitor for spread, and be prepared to remove it if necessary. If in doubt, choose a less risky alternative.