About
Alder here is the Eastern riparian workhorse Alnus serrulata — a nitrogen-fixing birch relative that laughs at wet feet while feeding streambanks. Catkins look like fuzzy earrings; roots partner with Frankia bacteria so you can stop pretending only legumes fix N. In subtropical and tropical Americas it lines seeps, pond edges, and stormwater cuts where "ornamental turf" would drown or lie. Other Alnus species exist; match site to native range. ☀️💧 Sun and Water Requirements: - Full sun to light shade along wet edges. - Saturated to moist soils; tolerates seasonal flooding better than drought. - Not for dry sandhill unless you enjoy watching sticks die. ✂️ Methods to Propagate: - Seeds: needs moisture stratification; sow in wet media. - Hardwood cuttings: treated cuttings in humid conditions for some species; seed easier for serrulata in restoration contexts.
Permaculture Functions
- Nitrogen Fixer: Feeds successional plantings cheaply.
- Wildlife Attractor: Seeds and cover for birds; early pollen for insects.
- Erosion Control: Roots knit soggy banks.
- Mulcher: Leaf litter feeds aquatic and riparian food webs.
- Water Purifier: Riparian buffer strips intercept runoff when planted as bands.
Alder is wetland infrastructure with chemistry:
Practitioner Notes
- Fixes nitrogen via Frankia actinobacteria, not rhizobial inoculant packets meant for beans and peas.
- Bare-root seedlings desiccate in minutes on a breezy day—plant mud-to-mud if possible.
- Catkins drop early-season pollen when many fruit species are still dormant—useful insect wake-up food along wet edges.
Companion Planting
- Willow
- Elderberry
- Swamp sunflower
- Roof drip lines on dry berms
- Planting as a street tree under power lines without space
Pest Pressure