Plant library · Ornamental & Flowering Trees
Ilex opaca
American holly is an evergreen ornamental tree that brings a strong vertical presence to a planting plan, eventually reaching about 30 feet tall and 15 feet wide. Its spiny foliage holds structure through winter, while red berries add seasonal color when fruit set occurs. Use it where a permanent, full-size tree can remain part of the garden’s framework rather than as a temporary filler.
Place American holly in a full-sun position where its broad, evergreen outline can anchor the back of a large bed, define a property edge, or stand clear as a specimen. Keep the lower canopy away from narrow routes, play areas, and entries so the spiny leaves do not crowd everyday circulation. Its mature height can cast substantial shade, so reserve the south side of nearby sunny planting areas for lower-growing plants or open ground.
Set plants 12 feet apart, center to center, when creating a repeated row or screen. Each tree can reach about 15 feet wide, so this spacing allows mature canopies to meet and form a continuous evergreen presence. For a specimen, leave a wider clear zone around the tree’s eventual 15-foot footprint and keep paths, walls, and other long-lived trees outside that space.
Give this tree full sun and moderate water, especially while it is establishing its permanent root zone. Plan the site with drainage in mind: American holly performs best in moist but well-drained ground and is poorly suited to persistently saturated or poorly drained areas. Avoid alkaline or limestone-influenced soil where possible, since foliage may yellow there.[1]
Late-spring to early-summer bloom is followed by the possibility of red winter berries. Fruit requires both male and female plants, so include a compatible male pollinator nearby when winter display is a goal. The evergreen canopy remains visually present throughout the year, making its spacing and shade pattern a permanent part of the plan.
The leaves carry sharp spines, so give American holly a buffer from paths, gates, seating, and places where people routinely brush past the branches. In exposed winter sites, use a location sheltered from cold winds and intense winter sun. Do not place it close to the house in areas where defensible-space planting is a primary fire-planning concern.[1]
Editorial content updated 2026-07-20.