PSC 2620: Woody Trees and ShrubCourse HomeWeek 4

Corylus ps. - Filbert or Hazelnut

Plant Viewer
The leaves are ovate or cordate in shape with doubly serrated margins. The bark is flaky on Corylus colurna
There are both male and female flowers on the same plant. The male catkins are showy, but the female flower is hardly noticeable. Image: Wikipedia.org Husks surround the hazelnut as it forms. Image: Wikipedia.org

Plant Description

Corylus, also known as the Filbert or Hazelnut, is a small tree or large shrub (12-15 feet tall and 8-12 feet wide). While some are available in single-stem form, most Filberts are available in a multi-stem form. It has an upright and rounded form, with an open base where leafing is more sparse. It grows well in full sun in dry soil.

The 2-4 inch long leaves are dark green and broadly ovate or cordate in shape. The margin of the leaf is doubly serrated. The underside of the leaf is pubescent, with the top side being slightly pubescent as well. Both male and female flowers appear on a single plant in the spring. The male flowers are long catkins, which can be quite showy; the female flowers are red, but very small and inconspicuous.

Fruit begins to form on the plant in the summer, with a somewhat-showy green husk encasing the nut during the summer. The fruit, a hazelnut, ripens in the fall and is edible and grown as a commercial crop.

Landscape Use

Its form makes it a great selection for shrub borders or for use in a naturalized planting bed. Also a good, non-messy fruit producing plant.

Points of Interest

It is susceptible to blight, especially in moist climates.

Notable Cultivars

Corylus maxima Purpurea - Purple Giant Filbert A large shrub (15-20 feet high) with dark purple leaves in spring, fading to dark green in the summer.


Corylus avellana Contorta - Harry Lauder's Walking Stick The stems are extremely twisted and contorted. The branching pattern provides a great accent during the winter months.


Corylus avellana - European Filbert Grows up to 20 feet tall and forms a very dense shrub. One of the most productive fruit producers, with nuts that are of a good size and flavor.


Corylus colurna - Turkish Filber This tree form of Filbert can grow up to 40 or 50 feet tall. It is upright, almost columnar in nature, and is an excellent selection for difficult areas such as parking strips or island plantings because of its tolerance of poor soil. Not utilized enough in modern landscapes.