Light Needs
Mature Height
Mature Spread
Growing Zones
The Hazel Alder is an early bloomer that provides visual interest and supports animals, making it an invaluable addition to a yard. Also known as Alnus serrulata, this tree blooms in March and April. Male flowers are slim and green, and female flowers are red. Woody cones with scales replace the blooms and mature by fall. Green leaves fade into orange before dropping in the fall. Smooth, gray-brown bark provides color year-round.
Birds and deer feed on the cones throughout the winter when other food sources are scarce. Hazel Alder thrives in damp soil, making it a good pick for areas with increased moisture, like near ponds, streams, or marshy areas. This plant is native to North America, requiring little attention once acclimated. Grow the Hazel Alder in zones 4 through 9.
Hazel Alder Care
Choose a spot that receives full to partial sun and plant in rich, moist, well-drained soil. Water young trees for the first growing season, but established trees seldom need water, especially when grown in damp conditions. These trees are not heavy feeders, and fertilization is not required.
Remove dead or damaged growth as necessary. Hazel Alder trees have an excellent natural form and seldom need pruning or shaping.
Hazel Alder Spacing
The Hazel Alder reaches 10 to 20 feet tall and spreads 8 to 15 feet wide. Choose a spot away from powerlines or overhead obstructions. Space trees 10 feet apart.
Hazel Alder Plant Facts
Growing Conditions
- Hardiness ZonesGrowing Zones
- USDA Zones 4 to 9 (perennial); grown as an annual elsewhere (outdoors year-round); grown indoors elsewhere (outdoors year-round); grown in containers elsewhere (grown as a seasonal crop)
- Sun Exposure
- Part Sun to Full Sun (5+ Hours Direct Sun)
- Mature Height
- 10-20 Feet
- Mature Spread
- 8-10+ Feet
- Growth Habit
- , Upright
- Water Needs
- Average
Flowers & Foliage
- Flower Colors
- , Green, Red
- Flower Description
- Green male and red female flowers
- Bloom Time
- Late Winter to Early Spring
- Blooms On
-
Old Wood
?
"Blooms on" tells you which stems produce flowers, which decides when it's safe to prune.
- New Wood: Flowers form on stems that grow this season. Prune in late winter or early spring without losing blooms.
- Old Wood: Flower buds form on last year's stems. Prune right after flowering. Pruning in fall or early spring removes next year's blooms.
- Both New and Old Wood: Blooms on last year's stems and again on new growth, so it flowers even after a hard winter or a mistimed pruning. Prune lightly after the first flush of blooms.
- When to Prune
- Right after flowering
- Foliage Color
- , Green, Orange
- Foliage Description
- Green, Orange
- Foliage Type
- , Deciduous, Variegated
- Seasonal Interest
- , Fall Flowering, Fall Interest, Winter Interest, 3 Season Interest
Garden Benefits
Plant Overview
- Common Name
- Hazel Alder
- Also Known As
- Smooth Alder, Tag Alder
- Botanical Name
- Alnus serrulata
Simple Plant Spacing Calculator
Please Note: The pictures below are to give a general representation of the different container sizes. The actual size/ages of plants are estimates and will vary based on type of plant, time of year, last pruning & many other factors.
Also Known As:
Quart
Plant Age:
~ 6 months - 1 year
Plant Size:
~ 4"-8"
Pot Size:
~ 4.75"H x 4.5"W
Volume:
1.50 quarts
Also Known As:
2.5 Quart Pot
Plant Age:
~ 1 - 2 years old
Plant Size:
~ 8"-12"
Pot Size:
~ 6.5"H x 6.5"W
Volume:
2.20-2.30 quarts
Also Known As:
#1 Container
1 Gallon
Plant Age:
~ 1 - 2 years old
Plant Size:
~ 10"-14"
Pot Size:
~ 7"H x 7.75"W
Volume:
2.26-3.73 quarts
Also Known As:
#2 Container
2 Gallon
Plant Age:
~ 1.5 - 3 years old
Plant Size:
~ 12"-18"
Pot Size:
~ 9.5"H x 9.5"W
Volume:
1.19-1.76 gallons
Also Known As:
#3 Container
3 Gallon
Plant Age:
~ 2 - 4 years old
Plant Size:
~ 12"-30"
Pot Size:
~9.5"H x 11"W
Volume:
2.32-2.76 gallons
Also Known As:
#5 Container
5 Gallon
Plant Age:
~3-4 years old
Plant Size:
~ 20" - 60"
Pot Size:
~11" H x 10 1/2” W
Volume:
3.5 - 4 gallons
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Plants that are currently in stock typically ship within 2-7 business days after your order is placed.
Plant Addicts ships to the lower 48 states within the U.S. Unfortunately, we do not currently ship to Alaska, Hawaii, or internationally.
This plant cannot be shipped to the following states: AK, HI. These restrictions apply only to this specific plant due to agricultural regulations or other limitations. Other plants may still be available for shipping to these states.
If you have any questions about shipping restrictions, feel free to reach out to our team!