Alders For Sale

Best Alnus In NZ!

Growing Alnus trees delivers a vast range of benefits:

• They are visual plants that add impact to a space.
• Alnus trees are nitrogen-fixing plants, which means that they can convert atmospheric nitrogen into a form that is usable by plants.
• They have deep roots that help to improve soil drainage and aeration as well as reduce erosion.
• They can be planted to create a windbreak or to create a privacy screen.
• Alnus trees provide food and shelter for a variety of wildlife, including birds, insects, and mammals.
• Street appeal can be greatly enhanced.
• Children can learn the plants and become more involved with nature.
• These plants will bring you pleasure for many years to come.

The Plant Company has an amazing range of Alder trees. From Common Alder, Evergreen Alders, Italian Alders, to Red Alders, we have the right tree for your space. Choose from a variety of Alnus that have been selected to thrive in NZ’s climate. We stock only the highest quality plants, sourcing them from NZ’s leading nurseries. Each plant is packed and transported with extreme care, ensuring it arrives to you in the same condition it was in when it left the nursery. If you are wanting to buy Alnus, shop with confidence from the best in the industry.

Alnus Questions

1. What is Alnus?

Alnus, also known as alder, is a genus of flowering trees and shrubs in the birch family. Alnus trees are native to temperate and cold regions of the Northern Hemisphere, but they have been introduced to many other parts of the world, including New Zealand.

2. What species of Alnus are grown in NZ?

There are several species of Alnus that are grown in New Zealand, including:

• Alnus glutinosa (common alder): A medium-sized tree with glossy green leaves and catkins.
• Alnus cordata (Italian alder): A medium-sized tree with heart-shaped leaves and catkins.
• Alnus jorullensis (evergreen alder): A large tree that remains evergreen.
• Alnus rubra (red alder): A large tree with reddish-brown bark and catkins.
• Alnus incana (grey alder): A medium-sized tree with grey bark and catkins.

3. Where can I grow Alnus?

Alnus trees can be grown in most parts of New Zealand, but they prefer moist, well-drained soil. Alnus can tolerate a variety of soil types, but tend not to do well in soils at the extremes of wet and dry. They are hardy to frost and cool climates which also makes them applicable to most regions.

4. How do I plant an Alnus?

To plant an Alnus, choose a sunny spot with moist, well-drained soil. Dig a hole that is twice as wide as the root ball of the tree. Place the tree in the hole and backfill with soil. Firm it in gently to remove any air pockets and water the tree well. Keep watering the tree until you are satisfied it has established and no longer at risk of drying out. Putting in a stake to support the tree along with mulching around the tree with bark chips are also advised.

5. How long does it take for an Alnus tree to grow?

Alnus trees are relatively fast-growing. They can reach a height of 10-15 metres within 10 years.

6. What is the fastest growing alder tree?

Alnus jorullensis (evergreen alder) is the fastest growing of the alders. It can reach 10 m tall inside of five years, and 20 m tall inside of 10 years. Its rapid growth rate makes it perfect for shelterbelts and for screening.

7. Are alder trees deep rooted?

Alder trees are deep rooted. They have a taproot system that can grow up to 2 metres deep which makes them very good at stabilizing soil and preventing erosion. Their root system also makes them very good at taking up water and nutrients from the soil, hence they are a good choice for planting in areas with poor soils.

8. Where are Alnus native to?

The genus Alnus, commonly known as Alder, are native to a wide range of regions across the Northern Hemisphere:

North America:

• Alnus rubra (red alder) is native to the Pacific coast, ranging from Alaska to California.
• Alnus serrulata (tag alder) is native to the eastern United States and Canada.
• Alnus viridis (green alder) is native to northern Canada and Alaska.

Europe:

• Alnus glutinosa (common alder) is native to nearly all of Europe, except for the extreme north and south.
• Alnus cordata (Italian alder) is native to the southern Apennine Mountains in Italy and the northeastern mountains of Corsica.

Asia:

• Alnus glutinosa and Alnus orientalis (oriental alder) are native to western Asia, including parts of Turkey, Iran, and the Caucasus Mountains.
• Alnus japonica (Japanese alder) and Alnus hirsuta (Manchurian alder) are native to northern and eastern Asia, including Japan, Korea, and China.

Africa:

• Alnus glutinosa is native to parts of northern Africa, including Morocco and Algeria.

South America:

• Alnus acuminata (South American alder) is native to parts of South America, including the Andes Mountains.

It's important to note that some species of alder have been introduced and naturalized in regions outside their native range. For example, Alnus glutinosa is now found in parts of North America and Australia.

9. What is the English name for Alnus tree?

The English name for the Alnus tree depends on the specific species. Some common English names for various Alnus species include:

• Common alder: Alnus glutinosa
• Red alder: Alnus rubra
• Tag alder: Alnus serrulata
• Green alder: Alnus viridis
• Italian alder: Alnus cordata
• Oriental alder: Alnus orientalis
• Japanese alder: Alnus japonica
• Manchurian alder: Alnus hirsuta
• South American alder: Alnus acuminata

However, sometimes "Alnus" itself is used as the English name for the tree. This is especially common when referring to the genus overall, rather than a specific species.

We have an amazing range of fantastic plants that are ready for you!

10. How tall does an Alnus tree grow?

The height of an Alnus tree depends on the specific species and the growing conditions. Here are some typical heights for the common species:

• Common alder (Alnus glutinosa): 40-80 feet (12-24 metres)
• Red alder (Alnus rubra): 60-100 feet (18-30 metres)
• Tag alder (Alnus serrulata): 20-40 feet (6-12 metres)
• Green alder (Alnus viridis): 15-20 feet (4.5-6 metres)
• Japanese alder (Alnus japonica): 20-50 feet (6-15 metres)
• Manchurian alder (Alnus hirsuta): 20-60 feet (6-18 metres)
• South American alder (Alnus acuminata): 30-60 feet (9-18 metres)

Soil quality, water availability, sunlight exposure, wind exposure, and temperature all affect the rate of growth of Alnus trees and often their mature size.

11. What is alder good for?

Alder trees offer a variety of benefits both ecologically and commercially. Here are some of the ways alder is used:

Ecological benefits:

• Nitrogen fixation: Alder trees have symbiotic relationships with nitrogen-fixing bacteria in their roots. These bacteria convert atmospheric nitrogen into a form usable by plants, enriching the soil and improving fertility.
• Erosion control: The dense root systems of alder trees help to stabilize soil and prevent erosion, especially on slopes and riverbanks.
• Habitat creation: Alder trees provide food and shelter for a variety of wildlife species, including birds, insects, and small mammals.
• Wetland restoration: Alder trees can be used to restore degraded wetlands by improving water quality, reducing erosion, and providing habitat for wetland species.

Commercial uses:

• Wood: Alder wood is lightweight, strong, and has a beautiful grain. It is used for a variety of purposes, including furniture, cabinets, flooring, and musical instruments.
• Charcoal: Alder charcoal is prized for its high heat and long burning time. It is used in grilling and smoking.
• Fuel: Alder wood can be burned as a fuel source for heating homes and generating electricity.
• Medicinal uses: Alder bark and leaves have been used in traditional medicine for centuries to treat a variety of ailments, including pain, diarrhoea, and inflammation.

Additional uses:

• Landscaping: Alder trees are often planted as ornamental trees in parks and gardens. They are attractive and provide shade and privacy.
• Food: The cones of some alder species can be eaten, and the bark can be used to make a tea.
• Crafts: The smooth bark of alder trees can be used to make baskets, bowls, and other crafts.

Overall, alder trees are a valuable resource that has a wide range of uses. They are important for the environment, provide valuable products for humans, and are beautiful and interesting trees to have around.

12. Is Alder very hard wood?

Alder is not considered a very hard wood. It is classified as a "medium-density hardwood" or a "soft hardwood." This means it is harder than some softwoods, such as pine and cedar, but softer than most other hardwoods, such as oak and maple.

Here are some specific details about the hardness of alder:

• Janka Hardness: 570 lbf (2,515 N)
• Specific Gravity: 0.47
• Mohs Hardness: 2.0-2.5

For comparison, here are the Janka Hardness of some other common woods:

• Oak: 1,290 lbf (5,740 N)
• Maple: 1,450 lbf (6,450 N)
• Pine: 380 lbf (1,690 N)
• Cedar: 300 lbf (1,330 N)

Despite its relatively soft nature, alder has several qualities that make it a desirable wood for certain purposes.