Dreaming of harvesting your own delicious hazelnuts right from your backyard? The prospect is exciting, but before you dig in, understanding the mature size of a hazelnut tree is crucial. This knowledge will help you choose the right varieties, plan your planting space, and ensure your future nutty bounty thrives.
Many people envision a towering, majestic tree when they think of nut production. However, hazelnut trees often present a more manageable stature, making them a fantastic option for home gardens and even smaller landscapes. But ‘manageable’ can still mean a significant presence. So, how big does a hazelnut tree *actually* grow? Let’s explore the fascinating growth habits of these productive plants and what you can expect.
Understanding Hazelnut Tree Growth Habits
When we talk about how big a hazelnut tree grows, it’s important to understand that ‘tree’ is sometimes a bit of a misnomer. While some varieties can be trained into a single-trunked tree form, many hazelnuts naturally grow as large shrubs, forming multi-stemmed bushes. This shrubby habit is a primary factor in their overall size and spread.
Species and Varieties Matter
The first key to understanding hazelnut tree size is recognizing that there isn’t a single answer. Different species and cultivars of hazelnut (Corylus genus) have distinct growth habits. The most common species cultivated for their nuts are:
- Common Hazelnut (Corylus avellana): This is the European species and the most widely grown commercially. In its natural state, it typically forms a large, spreading shrub, often reaching 10-20 feet (3-6 meters) in height and a similar width. With pruning and training, it can be managed to resemble a small tree with a single trunk, but its natural tendency is bushy.
- American Hazelnut (Corylus americana): Native to eastern North America, this species is generally smaller than its European cousin, usually growing 6-15 feet (1.8-4.5 meters) tall and wide. It’s known for its suckering habit, often forming dense thickets, which makes it excellent for wildlife habitat but requires management for optimal nut production in a garden setting.
- Filbert (often referring to cultivars of Corylus avellana or hybrids): The term ‘filbert’ is frequently used interchangeably with ‘hazelnut,’ especially in commercial contexts. Cultivars bred for specific nut qualities can vary in size, but most fall within the 10-20 foot range. Some modern cultivars are selected for more compact growth.
- Beaked Hazelnut (Corylus cornuta): This species, with its distinctive ‘beaked’ husk, is another North American native. It’s typically a smaller shrub, ranging from 5-10 feet (1.5-3 meters) in height and spread.
When you purchase a hazelnut plant, it’s usually a cultivar derived from one of these species, often Corylus avellana or hybrids. Always check the specific cultivar’s characteristics, as breeders often select for desirable traits, including size.
Factors Influencing Hazelnut Tree Size
Beyond the inherent genetics of the species and cultivar, several environmental and horticultural factors significantly influence how big your hazelnut tree will grow:
1. Pruning and Training
This is perhaps the most impactful factor for home growers. Hazelnuts are remarkably adaptable to pruning. You have two primary choices:
- Shrub Form: If you allow your hazelnut to grow naturally, it will develop into a multi-stemmed shrub. This is the easiest and often most productive form for home harvesting. The size will be dictated by its natural growth habit, usually 10-20 feet tall and wide. Regular thinning of older, less productive stems and removal of suckers will help maintain health and productivity, but won’t drastically reduce its overall potential size.
- Tree Form: You can train a hazelnut to grow with a single trunk, mimicking a traditional tree. This requires selecting a strong central leader when the plant is young and removing all other suckers and competing stems. You’ll also need to prune for a desired canopy shape. Training to a tree form can sometimes result in a slightly taller, more upright specimen than its bushy counterpart, but its ultimate height is still limited by its genetics, typically topping out around 15-25 feet (4.5-7.5 meters) depending on the cultivar and rootstock (if any). Removing lower branches to create a clear trunk will influence its perceived size and make harvesting easier.
Consistent pruning is key. For a tree form, you’ll prune annually to maintain structure and remove any unwanted growth. For a shrub form, annual thinning of older stems and suckers will improve air circulation, sunlight penetration, and nut production, while also managing its spread. (See Also: How Big Does Apple Tree Grow )
2. Soil Conditions and Fertility
Like any plant, hazelnuts thrive in good soil. Well-drained, fertile soil rich in organic matter will support more vigorous growth. Conversely, poor, compacted, or nutrient-deficient soil will stunt growth, resulting in a smaller, less productive plant.
Ideal Soil:
- Loamy or sandy-loam texture
- Slightly acidic to neutral pH (5.5-7.0)
- Good drainage (hazelnuts dislike waterlogged roots)
- Rich in organic matter
If your soil is poor, amending it with compost and well-rotted manure before planting, and top-dressing annually, will make a significant difference in its growth potential. Regular feeding with a balanced fertilizer in spring can also promote healthy development, but avoid over-fertilizing, which can lead to excessive leafy growth at the expense of nut production and can make the plant more susceptible to pests and diseases.
3. Sunlight Exposure
Hazelnuts are sun-lovers. For optimal growth and nut production, they need at least 6-8 hours of direct sunlight per day. While they can tolerate partial shade, growth will be slower, and nut yields will be reduced. In deep shade, a hazelnut will likely remain significantly smaller and may not produce many nuts at all.
Full sun encourages dense foliage, strong stems, and abundant flower development, all of which contribute to a larger, more robust plant.
4. Water Availability
Consistent moisture is vital, especially during the establishment phase and during fruit development. While mature hazelnut plants are relatively drought-tolerant once established, prolonged dry spells can stress the plant, leading to reduced growth and smaller nuts.
Watering Schedule: (See Also: How To Hang Christmas Tree Ornaments )
- Newly Planted: Water deeply 2-3 times per week for the first few months, ensuring the soil stays consistently moist but not waterlogged.
- Established Plants: Water deeply once a week during dry periods, especially from late spring through summer when nuts are forming.
Adequate watering supports healthy cell development, allowing the plant to reach its full size potential. Insufficient water will stress the plant, leading to stunted growth.
5. Climate and Growing Zone
Hazelnuts are generally hardy plants, but their optimal growth and nut production are tied to their preferred climate. Most common hazelnut varieties thrive in temperate climates with distinct seasons. Extreme heat or prolonged periods of frost can impact their vigor.
Most Corylus avellana and Corylus americana varieties are suitable for USDA hardiness zones 4 through 8. Planting outside these zones can lead to suboptimal growth. In hotter climates, they may struggle to achieve their full potential size and require more careful site selection (e.g., protection from intense afternoon sun) and consistent watering.
6. Pollination
While not directly affecting the *size* of the tree itself, proper pollination is critical for nut production, which is the ultimate goal. Most hazelnut varieties are not self-pollinating and require cross-pollination from another compatible variety. This means you’ll likely need to plant at least two different varieties that bloom at the same time. Adequate pollination leads to better nut set and development, contributing to the overall health and vigor of the plant, which indirectly supports its growth potential.
Expected Mature Size: A Summary
Let’s consolidate what we’ve discussed into practical expectations for mature hazelnut plants:
| Variety Type | Typical Height | Typical Width | Growth Habit |
|---|---|---|---|
| Common Hazelnut (Corylus avellana) – Shrub Form | 10-20 feet (3-6 m) | 10-20 feet (3-6 m) | Large, multi-stemmed shrub |
| Common Hazelnut (Corylus avellana) – Trained Tree Form | 15-25 feet (4.5-7.5 m) | 10-20 feet (3-6 m) | Single trunk, rounded canopy |
| American Hazelnut (Corylus americana) | 6-15 feet (1.8-4.5 m) | 6-15 feet (1.8-4.5 m) | Shrubby, often forms thickets |
| Beaked Hazelnut (Corylus cornuta) | 5-10 feet (1.5-3 m) | 5-10 feet (1.5-3 m) | Smaller shrub |
| Specific Cultivars | Varies (check plant tag/description) | Varies (check plant tag/description) | Can be more compact or vigorous |
It’s important to remember that these are *typical* sizes. A well-cared-for plant in ideal conditions might reach the higher end of these ranges, while a neglected plant in poor conditions might stay considerably smaller. Conversely, aggressive pruning can keep a plant smaller than its natural potential.
Planting Spacing Considerations
Knowing how big a hazelnut tree grows is essential for proper planting. For shrub forms, you’ll want to plant them at least 10-15 feet apart, depending on the expected mature width of the cultivar. If you are training them into individual trees, you can plant them slightly closer, perhaps 8-12 feet apart, but ensure they have room to develop their canopies without overlapping too much initially. (See Also: How To Remove Moss From A Tree )
If you’re planting a hedge of hazelnuts, spacing them 5-8 feet apart will allow them to grow together and form a dense barrier, but you will need to prune more aggressively to manage their size and shape.
Long-Term Management
The size of your hazelnut tree will also depend on your long-term management goals. Are you aiming for maximum nut yield? Are you trying to create shade? Or do you want a compact plant for a smaller garden? Your pruning strategy will dictate its final size and shape.
For Smaller Gardens: Choose compact cultivars if available, prune regularly to maintain size, and consider training to a single trunk to create a more defined, upright shape.
For Maximum Yield: Allow the plant to grow to its natural shrubby form, ensuring adequate spacing for air circulation and light penetration. Prune to remove old, unproductive wood and encourage new growth.
Understanding how big a hazelnut tree grows is not just about the numbers; it’s about understanding the plant’s potential and how to guide it to meet your gardening objectives. With the right care and knowledge, you can enjoy a generous harvest from a plant that fits perfectly into your landscape.
Conclusion
So, how big does a hazelnut tree grow? The answer is variable, typically ranging from 6 to 25 feet in height and width, depending on the species, cultivar, and how you choose to prune it. Most commonly, they form large shrubs 10-20 feet tall and wide, but can be trained into tree forms. Factors like soil, sunlight, water, and climate play significant roles in their ultimate size. By understanding these influences and managing your hazelnut plant appropriately, you can ensure it reaches its full potential, providing delicious nuts for years to come.
