“Weed morada” commonly refers to Purple Deadnettle (Lamium purpureum), a low-growing plant often found in gardens and landscapes, known for its distinctive purplish coloration. While sometimes considered a nuisance, this plant is widespread. This guide explores its identification, reasons for its appearance, garden impact, control methods, and beneficial aspects.
Identifying “Weed Morada”
The plant commonly known as “weed morada” is Purple Deadnettle (Lamium purpureum), a member of the mint family (Lamiaceae) characterized by its square stems. It typically grows 2 to 16 inches tall. Its leaves are triangular to heart-shaped with shallow lobes and a wrinkled appearance due to prominent cross-veining.
The upper leaves have a distinct purple or reddish hue, which intensifies with sunlight and gives the plant its “morada” (purple) designation. These leaves are covered in fine hairs, giving them a fuzzy texture. Small, tubular flowers, ranging from pink to light purple, emerge in whorls from the leaf axils near the stem tips.
Purple Deadnettle is often confused with Henbit (Lamium amplexicaule), another related plant with similar purple flowers. A key distinction lies in their leaves: Purple Deadnettle has triangular or heart-shaped leaves that are always stalked (petioled), even the upper ones. In contrast, Henbit’s upper leaves are more rounded or fan-shaped and directly clasp the stem without petioles.
Why “Weed Morada” Appears
Purple Deadnettle is a winter annual; its seeds typically germinate in the fall. Seedlings overwinter as small rosettes, then grow rapidly, flower, and produce seeds in late winter and early spring. The plants die back as temperatures rise in late spring and early summer. Some germination can occur in spring, and in mild climates, it may flower through winter.
This plant thrives in disturbed soils, common in gardens, fields, lawns, and roadsides. It prefers cool, moist conditions and often appears in areas with weak turf or recently tilled soil. Each plant can produce thousands of seeds, contributing to a persistent seed bank.
Impact on Your Garden
Purple Deadnettle can have both positive and negative effects in a garden. Its rapid growth and dense patches can compete with desired plants for water, nutrients, and sunlight. If left unchecked, it can smother cultivated plants, affecting their vigor and health, and disrupt the appearance of lawns or beds.
Despite these concerns, Purple Deadnettle offers several benefits. It serves as an early-season food source for pollinators like bees, providing nectar and pollen when other flowering plants are scarce. Its dense growth acts as a natural ground cover, helping to prevent soil erosion, particularly in fallow areas or during winter. The plant can also improve soil structure and suppress other weeds by occupying bare ground.
Effective Control Strategies
Managing Purple Deadnettle involves preventative measures and direct removal. For small infestations, hand-pulling is practical, especially when the soil is moist, as it makes removing the shallow root system easier. Remove the entire plant to prevent regrowth. Hoeing or light cultivation in the fall can eliminate seedlings before they produce seeds.
Preventative strategies create an environment less hospitable to Purple Deadnettle. Maintaining a healthy, dense lawn or garden with desirable plants suppresses weed growth by reducing space for germination. Proper lawn care, including appropriate mowing heights, regular fertilization, and deep, infrequent watering, promotes strong turf that outcompetes weeds. Aeration can also improve soil health.
For larger infestations, pre-emergent herbicides can be applied in late fall or early winter before seeds germinate. Post-emergent herbicides, such as those with 2,4-D or dicamba, can be used in early spring when the plant is actively growing. Always follow product labels and ensure compatibility with your grass type to avoid damage. Organic options, like pelargonic acid or acetic acid solutions (5% or greater), are available for spot treatments, though they are nonselective and can harm desirable plants.
Beneficial Aspects and Uses
Beyond its role in the garden ecosystem, Purple Deadnettle offers several beneficial aspects, including its edibility and traditional uses. The entire plant is edible; its leaves and flowers can be consumed raw in salads or cooked into dishes like soups, stir-fries, or pestos. Due to fine hairs, some find the texture more suitable when mixed with other greens or cooked.
In traditional herbal practices, Purple Deadnettle has been recognized for potential medicinal properties. It is described as having astringent, diuretic, and diaphoretic qualities. The plant also contains compounds with anti-inflammatory, antibacterial, and antifungal potential. Fresh, bruised leaves have been traditionally applied to minor cuts and wounds as a poultice. It can also be prepared as a tea or infusion.
Ecologically, Purple Deadnettle is one of the earliest flowering plants in spring. This early bloom provides a crucial food source for bees and other pollinators emerging from winter dormancy, helping to jump-start their foraging season. Its ability to flower even in mild winter conditions further extends this benefit. The plant’s presence contributes to local biodiversity and supports pollinator populations when other nectar sources are scarce.