Bog spurge (Euphorbia palustris)
Euphorbia palustris, or Bog spurge, offers showy, long-lasting yellow-green bracts in early summer. A low-maintenance, moisture-loving perennial ideal for rain gardens.
Complete Plant Information
Overview
Euphorbia palustris, commonly known as Bog spurge, is an upright, clump-forming herbaceous perennial valued for its bold texture and vibrant late spring color provided by large, greenish-yellow floral bracts. This plant thrives in damp conditions, making it a superb choice for challenging wet spots where many perennials fail. The showy display of Euphorbia palustris contrasts nicely with its medium green foliage, which often features attractive yellow and orange fall color.
Native to the marshlands of Europe and western Asia, Bog spurge offers reliable, low-maintenance performance across USDA Zones 5 through 10. It quickly establishes into an attractive 2 to 3-foot mound, integrating seamlessly into cottage gardens or naturalized settings. Its tolerance for wet soil and even shallow standing water cements its status as a workhorse for ecologically focused landscapes.
The visual impact of the flowers, which are actually modified leaves (bracts), lasts for an extended period through early summer. For gardeners seeking reliable structure and adaptable moisture tolerance, Euphorbia palustris proves to be an excellent, robust choice for bog gardens or rain garden installations.
Fast Facts
- Plant Family: Euphorbiaceae
- Plant Type: Herbaceous perennial
- Native Range: Europe, western Asia
- Hardiness Zones: USDA Zones 5-10
- Size at Maturity:
- Height: 2-3 ft
- Spread: 2-3 ft
- Bloom Time: June to July
- Bloom Description: Green with greenish yellow bracts
- Sun Exposure: Full sun to part shade
- Water Needs: Medium to wet
- Maintenance Level: Low
How to Grow
Plant Bog spurge in spring or fall in locations receiving full sun, though afternoon shade is appreciated in the hottest climates. The key to success for Euphorbia palustris is managing moisture; it prefers medium to wet, well-drained soils but is uniquely adapted to tolerate heavy, saturated soils and even shallow standing water. While established clumps handle some dryness, consistently damp locations are preferred for the best appearance.
Maintenance is generally low for this vigorous spurge. Clumps benefit from having spent flower heads removed after blooming to prevent unwanted self-seeding, though this is not mandatory. Be cautious when pruning or handling; the sticky, milky sap emitted by euphorbias can irritate the skin, so always wear gloves when working closely with this plant.
This versatile perennial handles poor soils well, including rocky-sandy mixes. While it tolerates heavier soils better than many other spurges, ensure drainage is adequate enough that roots are not sitting in stagnant, cold water year-round if possible. Gardeners in very hot, humid regions might observe some summer performance dips, reflecting its preference for cooler Mediterranean-type climates.
Landscape Uses
The remarkable adaptability of Bog spurge makes it highly valuable in contemporary garden designs focused on water management. Use it extensively for naturalizing areas that retain moisture, or as a primary structural component in rain gardens where it can absorb excess runoff. Its 2-3 foot height and upright habit also make Euphorbia palustris suitable for mixed perennial borders.
In woodland margins, it provides essential brightness against darker backgrounds, especially when combined with foliage plants that thrive in marginal wetness. For a cottage garden feel, pair the chartreuse bracts of Bog spurge with deep blues and purples from plants like irises, baptisia, or salvias that also appreciate ample moisture during the growing season.
Consider using its tendency to self-seed deliberately in naturalized drifts, allowing Euphorbia palustris to colonize damp, semi-wild areas effectively. Its ability to tolerate wildlife browsing, coupled with its bright summer coloration, ensures consistent interest throughout the growing season.
Standout Features
Flower Qualities
- Showy
Noteworthy Characteristics
Euphorbia palustris, commonly called marsh euphorbia or spurge, is an upright, clump-forming, herbaceous perennial that typically grows to 2-3’ (infrequently to 5’) tall and is native to marshland in Europe and western Asia. Although the true flowers are inconspicuous, they are subtended by large, long-lasting, greenish-yellow bracts which provide the exceptional showy color from June into July. Foliage emerges medium green, turning shades of yellow and orange/red as the season progresses, adding value beyond the bloom time.
Tolerances
- Rabbit
- Deer
- Drought
- Wet Soil
- Shallow-Rocky Soil
Potential Problems
Generally, Euphorbia palustris is quite resistant to serious diseases and common garden pests. The primary concern for gardeners involves its toxic sap; contact with the milky white latex can cause skin irritation or rashes, particularly in sensitive individuals, so always wear protective gloves when pruning or dividing the plant. Occasionally, opportunistic pests like aphids, mealybugs, or spider mites may appear, especially if the plant is stressed or if afternoon shade is excessive. Management usually involves mild insecticidal soap treatments for light infestations.
Frequently Asked Questions
What hardiness zones is Bog spurge suitable for?
Bog spurge, Euphorbia palustris, is hardy across USDA Zones 5 to 10.
How large does Euphorbia palustris grow?
This herbaceous perennial typically reaches a height between 2 and 3 feet, with a similar spread of 2 to 3 feet at maturity.
What sun exposure does Bog spurge need?
Euphorbia palustris prefers full sun but will tolerate part shade, although too much shade can cause the clumps to open up and lose their attractive shape.
When does Bog spurge bloom?
Bog spurge blooms from June into July, featuring flowers described as green with showy, greenish-yellow bracts.
Conclusion
The Euphorbia palustris is a resilient and visually rewarding perennial, offering reliable structure and unmatched color in reliably damp garden areas. As a low-maintenance option perfect for rain gardens, the Bog spurge merits inclusion wherever medium to wet soil conditions prevail. Before planting, confirm that your location’s hardiness zone falls between 5 and 10 to ensure optimal, colorful performance.
Companion Planting
When planning a border featuring Euphorbia palustris, select neighbors that share its moisture requirements but offer contrasting habits or bloom times. Plants that enjoy consistently moist feet, such as Siberian Iris (Iris sibirica) or certain varieties of Astilbe, can provide vertical contrast once the spurge’s bracts begin to fade. For a late-season interest near your Bog spurge, consider Joe Pye Weed (Eutrochium purpureum), which offers height and structural interest later in the summer while appreciating the ground moisture retained in rain garden settings.
Propagation Tips
Division is the most practical method for multiplying mature clumps of Euphorbia palustris. Dig up the established clump in early spring before new growth hardens off or in the early fall. Carefully separate the root ball into manageable sections, ensuring each division has healthy roots and some viable crown material. Replant immediately into prepared, moist soil. Be aware that while this species will self-seed, division is necessary to maintain desirable clump size and shape and to prevent overcrowding in the garden.
