Japanese maple (Acer palmatum 'Sherwood Flame')

Overview

Acer palmatum ‘Sherwood Flame’ is a highly coveted cultivar of the Japanese maple, prized for its consistently attractive, deeply lobed foliage that maintains a rich reddish-purple color throughout the spring and summer months. This deciduous shrub or small tree offers an excellent rounded-spreading crown, making it a superb focal point in refined garden settings. As a low-maintenance specimen, the appeal of the ‘Sherwood Flame’ lies in its dependable summer color, often superior in retention compared to similar cultivars.

This specific Japanese maple matures to a manageable garden size, typically reaching 14 to 16 feet tall with a spread of 12 to 14 feet. It performs best when provided with slightly acidic, organically rich, and well-drained soil conditions. While tough once established, thoughtful siting is key to ensure that the delicate new foliage of Acer palmatum ‘Sherwood Flame’ avoids scorching during intense summer heat.

Gardeners selecting Acer palmatum ‘Sherwood Flame’ benefit from its structure and year-round interest, particularly when its foliage shifts to a brilliant scarlet red in the fall. Its elegant form provides excellent texture and color contrast against evergreen backgrounds, cementing its role as a classic, structure-defining landscape plant.

Fast Facts

• Plant Family: Sapindaceae
• Plant Type: Deciduous shrub
• Hardiness Zones: USDA Zones 5-8
• Size at Maturity:
  • Height: 14-16 ft
  • Spread: 12-14 ft
• Bloom Time: April
• Bloom Description: Reddish-purple
• Sun Exposure: Full sun to part shade
• Water Needs: Medium
• Maintenance Level: Low

How to Grow

The ideal time for planting your Japanese maple, including the ‘Sherwood Flame’ cultivar, is during the cooler seasons—fall or early spring—to allow roots to establish before summer stress. Site these trees where they receive moist, organically rich, slightly acidic, and very well-drained soil. While full sun is acceptable in cooler, northern regions, gardeners should prioritize part afternoon shade in hotter climates to prevent foliage scorch, especially when soils might dry out.

Consistent moisture management is essential for Acer palmatum ‘Sherwood Flame’. Water regularly to keep the soil consistently moist, particularly during dry spells; mulching around the base is highly recommended to conserve soil moisture and keep the shallow root system cool. Fertilize lightly only in the spring before the leaves fully emerge. Protection from strong winds is also vital for preventing physical damage to the branches and leaves.

Pruning should be kept to an absolute minimum for this specimen. If shaping or deadwood removal is necessary, perform the work in late fall or mid-winter when the plant is fully dormant. Avoid pruning during the spring or summer, as this frequently causes significant sap “bleeding” from the cuts.

Landscape Uses

Japanese maples, and specific cultivars like the striking Acer palmatum ‘Sherwood Flame’, are primarily cultivated for their exceptional foliage display and elegant structure. They shine brightest when utilized as specimen or accent trees, drawing the eye to key areas near entryways or patios. Their moderate mature size makes them perfect for placement at the periphery of borders where they can create soft screening.

Consider planting ‘Sherwood Flame’ in woodland garden margins where it can benefit from dappled sunlight throughout the day while enjoying the protection offered by taller canopy trees. Due to their refined appearance, group plantings around the home foundation or yard periphery create a cohesive, sophisticated look. Bonsai enthusiasts also find the leaf structure and growth habit of the Japanese maple highly desirable.

When selecting companions, prioritize plants that thrive under similar slightly acidic, consistently moist conditions. Underplanting with shade-tolerant groundcovers like Japanese forest grass or shade-loving perennials can provide a lush foundation that complements the texture and dark summer color of the ‘Sherwood Flame’.

Standout Features

Flower Qualities

• Insignificant

Noteworthy Characteristics

Acer palmatum, commonly called Japanese maple, is a deciduous shrub or small tree that typically grows to 10-25’ (infrequently to 40’) tall. General plant form is rounded to broad-rounded, often with low branching. ‘Sherwood Flame’ (Matsumurae Group) is a small tree with a rounded-spreading crown that is particularly noted for its attractive reddish-purple foliage which retains excellent color throughout spring and summer before finishing in scarlet red fall tones. Each palmate leaf has seven serrated lobes which taper to sharp terminal points, and the clusters of red samaras in fall are unusually showy features of this cultivar.

Tolerances

• Rabbit
• Black Walnut

Potential Problems

This Japanese maple faces several potential issues related to climate and pests. Foliage is susceptible to damage from late spring frosts because the leaves tend to emerge early each year. To mitigate this, protect new growth if frost is expected after bud break.

Pest concerns may include mites, aphids, scale, borers, and root weevils, requiring routine inspection, especially during hot, dry spells. Fungal and vascular diseases such as Verticillium wilt, stem canker, and root rots can also pose threats. Good air circulation, avoiding overhead watering, and selecting a well-drained site are the best cultural defenses against these problems.

In soils with a high pH level, the Acer palmatum ‘Sherwood Flame’ is prone to chlorosis, which presents as yellowing leaves due to nutrient lockout. Correcting soil pH through acidification amendments is the standard approach to resolving this physiological issue.

Frequently Asked Questions

What hardiness zones is Japanese maple suitable for?

Acer palmatum ‘Sherwood Flame’ is well-suited for USDA Hardiness Zones 5 through 8, offering reliable performance across these areas.

How large does Japanese maple grow?

This specific cultivar typically matures to a height between 14 and 16 feet, with a spread ranging from 12 to 14 feet wide, maintaining a rounded-spreading crown.

What sun exposure does Japanese maple need?

This plant thrives in full sun to part shade, but southern gardeners should ensure it receives afternoon shade, especially during periods of intense summer heat, to protect its foliage.

When does Japanese maple bloom?

The blooms on the Acer palmatum ‘Sherwood Flame’ occur in April, presenting as small, reddish-purple flower clusters.

Conclusion

The Acer palmatum ‘Sherwood Flame’ remains an outstanding selection for gardeners seeking low-maintenance beauty defined by exceptional foliage retention. Its vibrant reddish-purple leaves create year-round appeal, making the Japanese maple a superb choice for focal points or texture contrast. Before planting, confirm your site offers consistently moist, well-drained soil and sufficient protection from harsh afternoon sun or strong winds.

Companion Planting

Selecting appropriate neighbors enhances the performance and aesthetic of your Japanese maple planting. Since Acer palmatum ‘Sherwood Flame’ requires consistency in soil moisture and prefers slightly acidic conditions, look for woodland edge plants that share these needs. Astilbe, Hosta cultivars with heavy substance (to resist slugs), and bleeding hearts all thrive in the filtered light preferred by this maple.

These companions often share similar root structures or growth habits, avoiding root competition that can stress the shallow-rooted Japanese maple. Grouping these shade-tolerant perennials around the base also helps shade the soil, further supporting the moisture regulation critical for sustained health.

Seasonal Care Calendar

Spring preparation involves an acidic fertilizer application just before the leaves emerge, followed by careful watering if spring rains are insufficient. Monitor closely for late frosts, which can damage the emerging tender foliage of the ‘Sherwood Flame’.

Summer care centers entirely on consistent hydration; avoid letting the soil dry out completely, as this invites leaf scorch and mite infestations. Summer is also the best time to confirm pest activity and treat as necessary before problems become severe.

In late fall to early winter, perform any necessary pruning to remove crossing or dead branches, adhering strictly to the practice of avoiding spring or summer cuts to prevent sap bleeding. Winter protection involves ensuring mulch is adequate to insulate the roots through cold snaps.