Quercus ilex (Holm Oak)

Quercus ilex (Holm Oak) is a large evergreen tree adorned with a massive, rounded crown, often with a prominent umbrella form. The leathery leaves, 3 in. long (7 cm), are shiny dark green on top, covered with gray or yellow hairs beneath. Spiny-edged when young (resembling holly leaves), they become smooth-edged with age.

Quercus ilex (Holm Oak) is a large evergreen tree adorned with a massive, rounded crown, often with a prominent umbrella form. The leathery leaves, 3 in. long (7 cm), are shiny dark green on top, covered with gray or yellow hairs beneath. Spiny-edged when young (resembling holly leaves), they become smooth-edged with age. Inconspicuous yellow-green flowers (females in small clusters and males in dangling catkins) can be seen to hang off the tree in abundance in early spring. The female flowers give way to small egg-shaped acorns which are a valuable source of food for small mammals and birds. The gray bark of the trunk and branches is nearly smooth or finely cracked. A magnificent and picturesque shade tree or street tree. Resistant to salt-spray from the sea, Holm Oak is often planted as a hedge or windbreak in coastal areas. A great oak species for Western gardens.

  • Grows up to 40-70 ft. tall and wide (12-21 m).
  • A full sun to part shade lover, this tree is easily grown in rich, moist, well-drained soils. Drought tolerant once established.
  • Virtually disease free. Keep an eye out for aphids and leaf-mining moths.
  • Propagate by seed sown in a coldframe or seedbed as soon as ripe or by grafting in mid-autumn or late winter.
  • Toxic to horses.
  • Native to the Mediterranean region.

Requirements

Hardiness 7
– 10

Heat Zones 2
– 9

Climate Zones 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
Plant Type Trees
Plant Family Quercus – Oaks
Exposure Full Sun, Partial Sun
Season of Interest Spring (Early,Mid,Late)Summer (Early,Mid,Late)FallWinter
Height 40'
– 70'
(12m
– 21m)
Spread 40'
– 70'
(12m
– 21m)
Water Needs Average
Maintenance Low
Soil Type Chalk, Clay, Loam, Sand
Soil pH Acid, Alkaline, Neutral
Soil Drainage Moist but Well-Drained, Well-Drained
Characteristics Showy, Evergreen
Tolerance Drought, Salt
Garden Uses Hedges and Screens
Garden Styles Coastal Garden, Mediterranean Garden, Prairie and Meadow