Properties of Alder Trees – Alnus glutinosa
- Alder Trees – Alnus glutinosa, a deciduous broadleaf trees are one of the most common native woodland trees found in Ireland.
- It is a fast growing hardy tree that possesses the ability to grow well in a variety of sites and soils.
- It grows well in poor soils as it contains the ability to fix nitrogen which adds nutrients to poorer soils, in coastal areas where it can tolerate the salt spray and also in boggy and wet areas along riverbanks.
- They are considered a symbol of strength, wisdom and endurance.
- Leaves are shiny green that develop into leathery dark green as the plant matures. They are racquet shaped, turn brown in Autumn before falling off.
- Male and female flowers appear on the same tree in the form of catkins in late Winter months.
- Male flowers are the long catkins, whereas the female flowers are the small catkins that developed into the cone shaped fruit, that disperses seed during October.
- The bark of the Alder tree is rough, greyish in colour with fissures and cracks developing as the tree matures.
- Like Silver Birch, they are an ideal tree for screening in the garden, for breaking wind and provide a dense coverage along exposed parts of the garden as they are often feathered from the bottom.
- They are conical in shape and can grow up to 20 metres in height.
Benefits of Alder Trees to Biodiversity & Ecosystems
Planting an Alder tree is a fantastic way of helping the environment and encouraging biodiversity. They provide food and shelter to wildflower, insects, lichens and fungi. They grow well along riverbanks and in wetlands where ground is damp. The roots stabilise the riverbank and prevent soil from being washed away. The Alder trees provide many habitats and support a wide diversity of life, and are often home to otters and kingfishers.
How & When to Plant your Alder Trees – Alnus glutinosa
- Best planted in the Bare Root Season, typically between November and late March.
- We grow Alder Trees here in our native Nursery.
- When planting bare root plants, it is best to break up the soil really well and loose.
- Dig the hole and place the tree with the roots exposed in the hole.
- Be careful not to damage the Roots.
- Place the tree in the hole up to the collar of the tree.
- Shovel back in the loosed soil and firm the plant in place by walking in the plant.
- A good guide to follow is to have the soil loose enough for the water to get in, but not loose enough for the air to get in.
- To view a video of how to plant a bare root plant, Click here
After care for your Tree.
If planted in dry weather, trees should be watered regularly to ensure growth. Ideally, trees should be staked and secured with a super soft tree tie to give them added protection from the wind.
Soil: Any well draining soil, loves wet soil.
Status: Hardy in cold weather.
Position: Full sun, shade, tolerates shade
Flowering: Catkins in Spring