Hazelnuts, also known as filberts, are edible selections of the European Corulus avellana species. They can be grown as either a single trunk tree or in a shrub form, depending on your desired pruning method. As a tree, they have a strong, open structure and will grow up to 15-18 feet tall and wide. The round, ruffle-edged leaves are approximately 3-4 inches long and can produce a pleasant canopy of shade. Winter through spring you will notice catkins or male flowers hanging on the branches waiting to produce pollen in late spring. Hazelnuts are relatively hardy and do best in cold winter areas.
In late summer, you will see the nuts starting to ripen and then drop from the trees in early to mid-fall. Depending on variety, you will harvest either round or oblong nuts that formed inside the colorful, frilled husks. Any squirrels in the area will also be keenly aware of harvest season, so keep an eye out for agile nut thieves in September and October. Cross pollination is required for best fruit set, so make sure to plant two different varieties for best production.
Location
Open site in full sun, with good air circulation. In very hot summer climates, partial shade is recommended.
Soil
Deep garden, loamy soil works best - well drained, not soggy. Avoid heavy clay.
Planting
Space trees at 10-15 foot intervals. See bare root and container planting guide.
Water
To ensure steady fruit development from bloom to harvest, make sure to provide regular water throughout the growing season - usually a deep watering every 10-15 days depending on heat and sun exposure. Be sure to continue the regular deep waterings as the fruit begins to ripen and approach harvest.
Fertilizer
Use a balanced fertilizer in early spring with micronutrients to maintain consistent growth and fruit production. We recommend Anderson’s Best: That’s All It Takes, Fertilome Fruit, Nut and Pecan food, or Natural Guard Organic Fruit and Citrus Fertilizer. A good rule of thumb is to use 1/2 to 1 pound of fertilizer per inch of trunk diameter (2 cups generally equals 1 pound). Spread fertilizer
evenly around the drip line of the tree.
Pruning
Both the tree and shrub form of filberts tend to sucker each year, so clear those out in spring, and again during the summer as needed. The tree form grows more upright, so training as a central leader makes sense. Thin out any dead or damaged branches each spring, and remove up to 20% of the older growth each year, especially if the branches get overgrown and too dense in the middle of the tree. Otherwise, minimal pruning each year will be adequate to maintain a healthy crop.
Harvest and Yield
When ready for harvest, the nuts will fall from the husks and can be easily gathered up from the ground. Dry the nuts for 2-3 days in a warm, mostly sunny location. Hazelnuts can keep in-shell for up to 12-18 months if stored in a cool, dry place. Each tree will usually produce 20-30 pounds of nuts depending on location, fertilizer, variety and rootstock.
Pests
Aphids are the most common insect to attack hazelnut trees each summer. To best control the aphids, use a dormant spray/fungicide combo during the late dormant season or even just as the buds start to swell in early spring. During the growing season (even right up until harvest), apply a general-purpose insecticide as needed. Fertilome Fruit Tree Spray (organic), Sevin, or Malathion
are all excellent insecticides for the job. Lady Bugs will also do a great job at controlling aphid outbreaks. Otherwise, Hazelnuts are relatively pest and disease free in the Intermountain West.
Varieties
Hazelnut (Filberts), Barcelona
The Barcelona produces a very large nut that is round, and fine-flavored. This popular tree is a favorite among home growers, and it’s the nut of choice for commercial growers. Filberts are easy to grow and will succeed wherever it is possible to grow peaches and are comparable in size. These nuts are high in food value and will ripen in early September. Suckers will need to be removed or your tree will turn into a bush.
Mature Height: 15’-20’
Mature Spread: 15’-20’
Sun Exposure: Full – Partial
Flavor: Rich
Cooking/Storage: Good for both.
Bloom Period: Mid-season
Pollinator Required: Yes.
Harvest Period: Ealy September
Zones: 5-9
Hazelnut (Filberts), Hall's Giant
A good pollinator for other Filberts, Hall’s produces light crops of medium to large-sized, round nuts. Don’t be surprised if it skips a year of production every so often. It grows vigorously and will require sucker control if a tree-form is desired; its natural state is more of a shrub.
Mature Height: 8’-15’
Mature Spread: 8’-12’
Sun Exposure: Full - Partial
Flavor: One of the best.
Cooking/Storage: Good for both.
Bloom Period: Late winter – early spring
Pollinator Required: Yes.
Harvest Period: August - September
Zones: 4-8