Growing fruit and nut trees is a great way to introduce height, structure and a little natural privacy to a space. It also provides you with a supply of fresh produce and is one of the quickest and easiest plants to grow.
Attractive plants, the fuzzy, serrated heart shaped leaves are complimented in the spring by the emergence of yellow catkins. These are followed by papery husks in late summer or fall. As well as being a resilient, low maintenance choice these popular specimes don’t need as much room to flourish as other fruit trees. This makes them a great choice if space is at a premium.
Native to large parts of the Northern Hemisphere, in the wild the hazelnut tree thrives in cool, deciduous forests. Traditionally thought to be a symbol of wisdom, they are mentioned in ancient Greek and Roman mythology as well as in the Bible.
Today the hazelnut tree is commercially grown for its nuts. The wood is also useful. It can be turned into fencing, handles for tools and baskets. Meanwhile the oil from the common hazel is used in cosmetic and food products.
An attractive and versatile plant, with just a little effort the hazelnut tree provides you with a supply of sweet nuts throughout the summer months. Also known as filberts, this guide will take you through everything that you need to know about the hazelnut tree.
From early spring until late fall, the hazelnut tree brings interest and structure to the garden.
What is a Hazelnut Tree?
A member of the Betulaceae or birch family, hazelnut trees can be further categorized into the Corylus genus. In this genus you will find several different species, many of which produce the desirable, edible nut.
The most popular or commonly grown varieties are:
- C. Avellana also known as the European or common hazelnut,
- C. Maxima or the giant filbert,
- C. Americana, commonly known as the American filbert.
Of these 3 varieties, C. Avellana is commonly grown. A deciduous shrub it is easy to grow and provides year round interest. Common cultivars include Barcelona, a popular home garden and commercial choice. Barcelona produces large crops of rich nuts. A versatile plant it can also be grown as a shrub. A mature Barcelona hazelnut tree can reach up to 13 ft. Barcelona requires cross pollination by other cultivars for fruit to form.
Contorta or Harry Lauder’s Walking Stick is an ornamental variety, popular for its gnarled twisting branches. During the spring yellow catkins and green leaves emerge. In the fall the attractive foliage turns bright yellow.
Ennis is a high yielding hazelnut tree cultivar which produces large, flavorsome nuts. Susceptible to Eastern filbert blight it requires cross pollination with Hall’s Giant. While this is not a large cropping cultivar it does have a vigorous growth habit.
York is a pleasingly compact cultivar, producing averaged sized nuts. It also produces lots of attractive catkins and pollen during the spring and summer. This makes it a popular choice for the pollinator garden. Resistant to eastern filbert blight, York is compatible with a number of varieties.
The distinctive yellow catkins of the Hazelnut tree.
The C. Americana cultivar is a good choice for northern growers. These plants tolerate heat and cold well; they are also resistant to Eastern filbert blight. Creating a good windbreak, in the fall, the foliage turns attractive shades of gold, yellow, red and orange. For something truly different, Corylus maxima Purpurea produces purple foliage and purple husks.
Most species are hardy in USDA Zones 4 to 9. Depending on the plant and growing conditions they can achieve a height of between 8 and 20 ft. and a spread of around 15 ft. They can also be cultivated as small shrubs.
Like sycamores and zucchini plants, the hazelnut tree is monoecious. This means it produces male and female flowers on the same plant. However, they may not flower at the same time. American varieties, C. Americana, self-pollinate while European varieties, C. Avellana, are self-incompatible. This means that they do not self pollinate even though they produce male and female flowers.
Not all types of hazelnut tree cross pollinate. When selecting cultivars, consider the pollination recommendations. Even if you are planting a self-pollinating type it is recommended you plant more than one to help improve the yield.
How to Plant a Hazelnut Tree
You can grow your own hazelnut tree in one of a number of ways. You can purchase bare root saplings or potted shrubs from a reliable garden store or plant nursery. Alternatively you can grow the plants from runners harvested from an already established hazelnut tree or from seed.
Planting Bare Root Saplings and Potted Shrubs
If you are selecting your root or shrub in person, try to select the healthiest available specimen. Healthier plants are easier to establish in new positions. If you are ordering from an online store, the shrub or root will be sent to you when it is ready to plant.
Bare roots are best planted in late fall or early spring. Plants growing in pots can be planted at any time of year. However, they are best planted when dormant, during the winter or early spring. Transplanting dormant specimens helps to prevent heat stress and reduces the need for regular watering. Try to plant when the soil is workable and not frozen. The soil should be dry or damp. Don’t plant in water-logged soil.
Water the roots well before planting. Use a good shovel to dig hole twice as wide and twice as deep as the root ball. Position the root or plant in the center of the hole. The top of the roots should be just below the level of the soil.
Refill the hole, mixing in equal parts compost and peat moss or sand if the soil is a heavy clay type. As you fill, tamp down the hole to remove any air pockets.
After planting water well. Continue to water regularly until the plant is established and, if planting in the spring, new growth is visible.
Once established the plants can grow 13 to 24 inches a year.
Space each hazelnut tree 15 to 20 ft apart.
Growing a Hazelnut Tree From Seed
Growing from seed is a slow process. But it is also the cheapest. Seeds collected from trees in the wild, or from friends’ gardens cost nothing.
Before sowing, test the viability of the seed by placing it in water. Any seeds that float are not viable. These should be discarded.
Score the viable seeds. Use a sharp file to make small slashes in the outer coat. This makes it easier for roots to emerge, aiding the germination process.
Sow seeds in the fall in position. Plant the seeds 15 inches apart and 2 inches deep. The slightly pointed side should face downwards.
Mulch or use a cold frame to protect the seeds over winter. A mini greenhouse such as the Ohuhu Portable Mini Greenhouse can be used as a makeshift cold frame. It also enables you to harden off young plants while protecting them from various pests.
Alternatively, you can start the seeds undercover in 8 inch pots filled with fresh potting soil. Sow the seeds in the fall. As with sowing in the ground, sow the seeds roughly 2 inches deep. Moisten the soil and place in a light position.
Germination can take several months. During this period it is important that the soil isn’t allowed to dry out.
If you are keeping the pots in a cold frame or a sheltered area make sure that they don’t become waterlogged during rainy spells.
In the spring, when the weather is warm, water regularly to keep soil evenly moist. Seedlings should appear in a few weeks.
In warmer climates you may need to stratify the seeds. This means artificially exposing them to cold weather. To stratify, place the seeds in a zip-top bag filled with an even combination of peat moss and sand.
Place the bag in a refrigerator overwinter.
The following spring, move the bag to a warm place in the house for a few days or until signs of germination appear. After the seeds germinate, plant them in 8 inch pots filled with potting soil.
Keep the seedlings in their pots over the summer in a partial shade position. Remember to regularly water. After hardening off, you can transplant into the ground in fall or when seedlings are 8 to 10 inches tall.
Propagating a Hazelnut Tree from Runners
Runners are the suckers that appear at the base of an existing shrub. During the late fall, as plants are in the early stages of winter dormancy, dig up a sucker with its attached roots. Replant 15 ft apart, roughly 1 ft below the soil line. If you have access to an established hazelnut tree, this is one of the easiest methods of propagating and planting your own specimen.
Where to Plant
In hot, dry climates plant in a full sun or partial shade position. Generally the hazelnut tree needs at least 4 hours of direct sunlight every day. This encourages good nut production.
The soil should be well draining. Avoid planting in boggy or waterlogged areas. Work in organic material such as compost or sand to improve drainage. A soil pH of 5.5 to 7.5 is ideal. If you don’t know the make up of your soil, a soil test kit is a quick and easy way to find out. Avoid soil that is too rich in nutrients, this causes foliage to emerge at the expense of fruit.
While most varieties are hardy in USDA Zones 4 to 9 some can tolerate USDA Zone 3. However, temperatures falling below 15 ℉ can cause blossom drop.
Ensure that the plants have room to flourish.
Spacing specimens 15 to 20 ft apart gives them lots of room to spread out and develop.
Caring for a Hazelnut Tree
Once planted the hazelnut tree is a pleasingly low maintenance addition to the garden.
Mature specimens are drought tolerant. Young plants need regular water, so don’t allow the soil to dry out.
Water weekly during the growing season until the plants are established. Try to water 1 inch every 10 days for the first two seasons after planting.
Use a hose to ensure that you water deeply around roots during dry spells.
In good soil, no additional fertilization is required. If growth is slow, or the foliage appears pale a small dose of nitrogen fertilizer can be applied in spring.
The hazelnut tree can be shaped into a shrub or tree. This versatility means that they suit a range of growing situations and planting schemes.
Shrubs require little regular pruning. Remove any suckers that emerge at the base of the plant in the spring. This focuses the plant’s energy on creating a healthy main stem. A good pair of shears helps to keep plants in shape.
To encourage an open bush prune your hazelnut tree in winter. Aim to remove around a third of the oldest growth, cutting or sawing the stems down to ground level. Thin out any overcrowded areas. You are aiming to keep the center light and promote air circulation through the plant. Finally, cut back any crossing branches. Allow the young, twig-like foliage to remain in place, this bears the majority of female flowers.
To shape your hazelnut into a tree, remove the lower, hanging branches. Keep 3 to 5 stems at top of the main leader or trunk.
In the winter of the first season, when the plant is still dormant, identify the strongest or largest evenly spaced branches. Prune away the other branches and cut back any suckers. Continue to remove branches every year in late winter or early spring for a few seasons, until the leader branch reaches a decent height.
Common Pests and Problems
The hazelnut tree is a low maintenance specimen. However, there are a few things to watch out for.
Deer and rabbits enjoy eating the leaves, catkins and branches. Smart Spring Tree Guards provide robust protection against potentially destructive mammals. Squirrels also target nuts.
Squirrels love to take hazelnuts.
Filbert Worm or Acorn Moth (Cydia latiferreana) are small red-brown moths with a thin band across the wings. The large are half an inch long with beige or pink bodies and dark brown heads. Larvae overwinter in the soil before moths emerge the following spring, laying eggs on husks. After emerging the larvae like to eat the nuts, tunneling through and destroying whole kernels. This can ruin crops and cause bacterial or fungal pathogens to enter.
Nut Weevils (Curculio nucum) are beetles with elongated snouts. Adult beetles target buds and foliage during the spring before laying eggs on developing nuts in the summer. The larvae hatch and feed on nuts.
Damaged nuts rarely fall from the plant and can be harvested with other, healthy kernels. This ruins the entire crop. To naturally remove the nut weevils place a sheet of tarp under the foliage. This is best done in late summer after rainfall. Shake the plant to dislodge the adults before placing them in soapy water.
Planting in favorable conditions reduces the risk of disease.
Eastern Filbert Blight is caused by the Anisogramma anomala fungus. Initially causing cankers to form on branches and flowers the disease eventually leads to wilting and plant dieback. Remove and dispose of affected branches to prevent the disease spreading throughout the plant.
Armillaria Root Rot is caused by Armillaria mellea or oak root fungus. Affected foliage discolors and falls away before branches die back. Eventually the entire plant dies. Yellow mushrooms may also appear at the base. Once present Armillaria Root Rot is difficult to cure. Instead dig up and destroy affected specimens. Today many plant nurseries sell rootstock that is resistant to this disease.
Bacterial Blight damages young branches and kills foliage and buds. Caused by Xanthomanos campestris pv. Corylina bacterium, it spreads through infected plants, causing lesions to form. Remove and dispose of diseased branches.
Bacterial Canker is caused by Pseudomonas avellanae and is typically problematic in European varieties. Typically causing new growth to wither and foliage and buds to die, it can also cause gray foliage to appear on the bark. Cut and dispose of infected plant matter to prevent the disease spreading.
Never place infected foliage on the compost heap.
How to Harvest
It can take 3 to 4 years before plants mature enough to start producing nuts. When mature, the first harvest nuts fall as they ripen. Nuts grow as clusters known as burrs. They form as the foliage grows. You can start to harvest in the fall once the leaves and burrs start to change color. While the foliage turns attractive shades of yellow or orange, the burrs usually turn brown.
As nuts ripen, cut grass and tidy up the area below the plants. This makes collecting the nuts easier.
Rake up the nuts from the ground or place a sheet of tarp beneath the plant. This collects the nuts as they fall. Typically you can harvest ripe nuts from late September to October.
Allow the nuts to ripen on the plant.
Discard any damaged or empty nuts. To test how good the nuts are place them in fresh water. Good nuts sink to the bottom. Any that float to the top should be discarded.
Dry the nuts by spreading them out on trays in a warm, sunny spot for a few weeks. Turn them every few days. Once dry, scrape off the papery husks.
You can store nuts either in their shells or shelled. Nuts in their shells can be kept at room temperature for several months. Shelled nuts should be consumed within a few weeks. Alternatively, they can be refrigerated for up to one year.
To roast the fresh nuts, place them on a baking tray in the oven at 180° for 20 to 30 minutes. Check regularly and rotate for an even roasting. Remove from the oven when the papery skins come easily away from the nuts.
The hazelnut tree is a distinctive addition to the garden.
Easy to grow, the hazelnut tree is a great hedging and natural landscaping choice. The colorful catkins and flowers are popular with bees and pollinators. Like other nut or fruit trees their colorful fall foliage is also a good way to add color and interest to late season gardens.