Andromeda spp.

bog rosemary

Ericaceae Circumboreal northern hemisphere

Attracts Pollinators Container Friendly

Native to North America

SunFull Sun – Part Shade

WaterHigh

HardinessZones 2–6

Overview

Andromeda spp. is a genus of two species of low evergreen shrubs in the family Ericaceae, native to cold peat bogs and wet heathland across the northern hemisphere. Plants are slender and wiry, spreading by creeping rhizomes to form loose colonies 6-24 in (15-60 cm) tall. The narrow, leathery leaves 0.4-1.6 in (1-4 cm) long have strongly inrolled margins and a whitish, waxy underside, an adaptation to the waterlogged, low-nutrient ground. In late spring small urn-shaped flowers, pink to nearly white and 0.2-0.3 in (5-8 mm) long, hang in nodding terminal clusters on red stalks. These ripen to dry, rounded seed capsules. A. polifolia, bog rosemary, is circumboreal across northern Eurasia and North America, while A. glaucophylla of north-eastern North America has hairier, more blue-grey leaves. All parts contain grayanotoxins that are poisonous if eaten. The genus needs permanently moist, acid, peaty soil and declines quickly in dry or limy ground.

Native Range

Andromeda spp. is native to the cool temperate and subarctic northern hemisphere, in bogs and peatlands across northern Europe, northern Asia, and northern North America. A. polifolia circles the boreal zone, and A. glaucophylla occurs in north-eastern Canada and the north-eastern United States.

Suggested Uses

Andromeda spp. is grown in bog gardens, peat beds, rock gardens with acid moisture, and containers of ericaceous compost. The early flowers draw bumblebees and other cold-season pollinators. Its toxicity makes it less suited to gardens used by grazing animals.

How to Identify

Recognise Andromeda spp. by its low, wiry evergreen habit and narrow leathery leaves with tightly rolled-under margins and a pale, waxy lower surface. The nodding clusters of small pink urn-shaped flowers on slender red stalks in spring are characteristic. Its bog habitat and inrolled blue-green leaves separate it from the similar Kalmia spp. and from leatherleaf, Chamaedaphne spp..

Appearance

Size & Dimensions

Height6" - 2'

Width/Spread1' - 3'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~3 weeks

Spring Summer

Flowering occurs in late spring to early summer (roughly May-June in the north of the range), with the pink to white urn-shaped flowers held in nodding terminal clusters for two to four weeks. Cool conditions extend the display. Dry brown seed capsules persist into autumn after the flowers fade.

Detailed Descriptions

Flower Description

pink to white

Foliage Description

blue-green

Growing Conditions

Sun Requirements

SunFull Sun SunPartial Shade

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range3.5 - 5.5(Acidic)

357912

Soil Types

peat

Drainagewet

Water & Climate

Water Needs

High

Frost Tolerance

hardy

Care & Maintenance

Care Guide

Across the genus, Andromeda spp. needs constantly moist to wet, strongly acid soil rich in peat, in full sun to light shade. It grows naturally in sphagnum bogs and suits bog gardens, peat beds, and damp acid borders, but fails on alkaline or free-draining soils that dry out. Cool roots and high humidity favour steady growth, and the genus is fully cold-hardy. Plants spread slowly by rhizomes and need little feeding, as they are adapted to low-nutrient ground. Lime, drought, and heat are the main causes of decline.

Pruning

Pruning is seldom needed. A light trim after flowering keeps the wiry stems dense, and older straggly shoots can be cut back to encourage low branching. Spent flower clusters may be left to form seed capsules.