Spotted deadnettle (Lamium maculatum 'Cosmopolitan')
Lamium maculatum 'Cosmopolitan' (Spotted deadnettle) is a low-maintenance, mat-forming perennial perfect for deep shade areas.
Complete Plant Information
Overview
Lamium maculatum ‘Cosmopolitan’, commonly known as Spotted deadnettle, is a highly effective, mat-forming perennial prized for its low-growing habit and adaptability to difficult, shady conditions. This cultivar offers gardeners a compact option that spreads readily via rooting stems, creating dense ground cover ideal for suppressing weeds beneath taller plantings. It proves valuable due to its low maintenance needs and its ability to thrive where many other ornamentals struggle, particularly in heavy shade.
Blooming from May into July with delicate light pink flowers, Lamium maculatum ‘Cosmopolitan’ provides consistent performance without demanding excessive care. As an herbaceous perennial, it offers structure in the garden and is evergreen in warmer zones, ensuring year-round visual interest. Gardeners appreciate this Spotted deadnettle for its vigor when grown in suitable cool, moist, well-drained soils.
This particular variety, Lamium maculatum ‘Cosmopolitan’, is known for its compact size compared to other Lamiums. Its success lies in its tolerance for dry soil and deer pressure, making it a reliable solution for shaded borders or naturalized areas that require robust, spreading ground coverage.
Fast Facts
- Plant Family: Lamiaceae
- Plant Type: Herbaceous perennial
- Hardiness Zones: USDA Zones 3-8
- Size at Maturity:
- Height: 0.25-0.5 ft
- Spread: 1-2 ft
- Bloom Time: May to July
- Bloom Description: Light pink
- Sun Exposure: Part shade to full shade
- Water Needs: Medium
- Maintenance Level: Low
How to Grow
Planting Lamium maculatum ‘Cosmopolitan’ is best done in spring or fall when temperatures are moderate. Select a location that receives part shade to full shade, as this Spotted deadnettle dislikes intense afternoon sun which can cause leaf scorch. The soil should be average, medium moisture, and well-drained; it thrives particularly well in acidic loams that remain evenly moist. When spaced 6 to 10 inches apart, this ground cover will quickly knit together to form complete coverage.
Maintenance is generally low, fitting the needs of busy gardeners. Ensure consistent moisture, especially during establishment, though established plants show some drought tolerance. Fertilizing is rarely required if the soil quality is adequate. Be aware that Lamium maculatum ‘Cosmopolitan’ dislikes wet soils, especially during winter, and compacted grounds.
In summer, especially in hot and humid climates, the foliage of this Lamium may decline, a phenomenon called “melting out.” If unsightly bare patches appear, shear or cut the plants back to encourage fresh, new growth to emerge. This quick recovery makes care straightforward, even when environmental stress occurs.
Landscape Uses
Spotted deadnettle is an excellent choice for small-scale ground cover tasks within shady garden environments. It efficiently covers banks or borders, creating a dense, low carpet beneath shrubs and trees where lawn grass struggles. Although it excels as a ground cover, direct foot traffic should be avoided as Lamium maculatum ‘Cosmopolitan’ is intolerant of heavy wear.
Use this perennial as a textural element along shaded walkways or pathways, provided traffic is minimal. Its spreading nature means it can also function effectively as a tame edger, though its spread may require occasional trimming to keep it confined to its designated area. Furthermore, the attractive foliage and soft pink blooms make Lamium maculatum ‘Cosmopolitan’ a viable cascading element when incorporated into hanging baskets or containers in deep shade.
Standout Features
Flower Qualities
- Showy
Noteworthy Characteristics
Lamium maculatum, commonly called spotted deadnettle, is native to Europe and North Africa to West Asia. It is a mat-forming perennial ground cover that typically grows 5-8” tall but spreads indefinitely over time by sprawling stems which root in the ground as they go. Clusters of tiny, somewhat inconspicuous, two-lipped, red-purple (sometimes white or pink) flowers appear at the stem ends in late spring to early summer. The cultivar ‘Cosmopolitan’ is noted for its compact size, variegated foliage, pink flowers and spreading habit, acting as a miniature sport of Lamium ‘Shell Pink’.
Tolerances
- Deer
- Drought
- Heavy Shade
- Dry Soil
Potential Problems
This dependable plant generally faces no serious insect or disease issues in optimal conditions. Occasional pests like slugs and aphids may appear and warrant spot treatment if nuisance levels increase. Growers should watch for leaf blight and leaf spots, which often signal fungal issues, particularly when humidity is high or air circulation is poor. The most significant cultural issue for Lamium maculatum ‘Cosmopolitan’ is crown rot, which occurs when soils remain poorly drained and constantly wet, especially over winter. Avoid planting in soggy areas to ensure long-term health.
Frequently Asked Questions
What hardiness zones is Spotted deadnettle suitable for?
Lamium maculatum ‘Cosmopolitan’ is hardy across a wide range, suitable for USDA Zones 3 through 8.
How large does Lamium maculatum ‘Cosmopolitan’ grow?
This perennial typically achieves a height between 0.25 and 0.5 feet tall, spreading horizontally to cover an area between 1 and 2 feet wide.
When does Spotted deadnettle bloom?
Lamium maculatum ‘Cosmopolitan’ produces its light pink flowers during the late spring and early summer, usually blooming between May and July.
What sun exposure does Lamium maculatum ‘Cosmopolitan’ need?
This ground cover performs best when situated in areas receiving part shade to full shade throughout the day.
Conclusion
Lamium maculatum ‘Cosmopolitan’ stands out as a robust, low-maintenance ground cover, bringing reliable texture and soft pink blooms to the darkest corners of the landscape. Its tolerance for heavy shade and deer makes this Spotted deadnettle a gardener’s secret weapon for tough spots. Check your local USDA hardiness zone compatibility before planting, and ensure soils are well-drained for best results with your Lamium maculatum ‘Cosmopolitan’.
Companion Planting for Shady Gardens
Since Lamium maculatum ‘Cosmopolitan’ thrives in cool, moist, well-drained soil under shade, pairing it with plants that share these requirements ensures a cohesive, thriving garden border. Excellent companions include Hostas, which offer contrasting foliage texture and size, or ferns like Japanese Painted Ferns (Athyrium niponicum), which complement the low profile of the Deadnettle. Astilbes and Brunnera macrophylla also share similar cultural needs and provide complementary late-season color or striking blue foliage that contrasts beautifully with the variegation often found on Lamium.
Managing Summer Decline
The primary seasonal maintenance task for Spotted deadnettle involves managing summer stress. If high heat and humidity cause the foliage to yellow or melt out, do not hesitate to shear the plants back by half their height. This action encourages the plant to flush out denser, fresh growth, improving its appearance for the remainder of the season or preparing it for winter dormancy. Proper watering—aiming for medium moisture without sogginess—helps prevent leaf scorch that results from drying out too much in dappled sunlight.
