Hazelnut coffee, hazelnut spread, hazelnuts... The common hazel tree (Corylus avellana) is what we can thank for the delicious hazelnuts that we find ourselves enjoying. Though technically, the hazel is the nut produced by any plant in the genus Corylus, the common hazel is the most often used source. Even though we have a native species of Corylus in the United States, the common hazel (a non-native to the US) is still the go-to if you want to produce nuts.
Delicious treats are not the only reason people plant these trees, though. For years they played an important functional role in Europe for creating hedgerows. This is becoming popular in the United States since the hazel can take to pruning very well. These attractive flowering hedges become valuable food sources for birds and small mammals, making your landscape into a miniature wildlife reserve, which is always good.
The hazel is also highly valued for its aesthetic value; the interesting flowers are a conversation piece that draws the eye, but the real highlight comes from the twisting branches. This can be seen in an over-the-top exaggerated form in the amazing cultivar Corylus avellana 'Contorta,' also known as most commonly known as Harry Lauder's Walking Stick.
|Common Name||Common hazel, hazenut tree|
|Botanical Name||Corylus avellana|
|Plant Type||Deciduous shrub or small tree|
|Mature Size||20 ft. tall, and 10 ft. wide|
|Sun Exposure||Full sun to part shade|
|Soil Type||Moist, organically rich, well-drained|
|Bloom Time||Early spring|
|Flower Color||Yellow and brown (Male)|
|Hardiness Zones||4-8, USDA|
|Native Area||Europe and Western Asia|
Hazelnut Tree Care
The common hazel is a relatively carefree plant. One important thing to note is that depending on your intended use, you will need to invest in two trees, a male and a female, if you want to produce nuts. Hazels are monoecious and not self-pollinating. If you want a self-pollinating hazel, there are hybrid varieties available. Male and female trees are readily available online from specialty retailers specializing in fruit and nut trees.
You may or may not end up with bit of shell litter under your trees if you have multiple trees, which might bother you. If it does, you may need to clean up the shell refuse that your friendly critters left under the trees. Shells aren't the only thing they release: hazelnut trees are prolific pollinators.
Placing a hazel in a location that receives full sun most of the day will give you the best yield of flowers and nuts if that is what you are trying to achieve. It will tolerate part shade as well, but you will see a decrease in flower production.
The hazel tree is very adaptable, but it is best to avoid densely packed soils, clays, or rocky soils. Its preference would be to grow in sandy loams that drain rather well.
Keeping your hazel tree watered is important to ensure profuse flower and nut production. It will not tolerate drought and will need supplemental watering to remain a viable producer if you look forward to it fruiting during dry periods. Water it using the same standard rule to establish 10 gallons per inch of trunk diameter after planting. Using this method will keep your hazel green and blossoming in even the driest of weather.
Temperature and Humidity
Hazels are great at existing in temperate areas. They are not particularly good at resisting deep freezes, nor are they able to deal with extreme heat and humidity. They do a wonderful job of standing up to wind compared to many trees, but that is the only extreme they will do well in facing. If you want your tree to thrive, keep it in USDA zones 4-8.
For the best blooms and fruit production, give your tree an application of organic slow-release fruiting tree fertilizer in the fall.
The primary upkeep task for a hazelnut tree involves cutting away the suckers that all hazels seem to develop. You may actually want this if you are using your hazel for attracting wildlife and birds. The sucker growth will create a thicket and give shelter and a habit to the critters and feathered friends when they need it. If you'd prefer it not, cut the sucker growth and create a brush pile with it as a shelter, or if you are the crafty type, it is fantastic for all kinds of crafts, from basketry to wreathe making.
When pruning, be careful not to confuse suckers with lateral branches. Don't remove any branches that shield the trunk from sun exposure, or you will end up with irreversible, prolific sprouting.
Growing Hazelnuts in the Pacific Northwest: Pollination and Nut Development. Oregon State Extension Office.