Magnolia virginiana L.

Any discussion of the Sweet Bay seems to become snagged on the complex variation patterns across its wide, low-altitude range in eastern North America (see taxonomic note above). Tree or shrub, deciduous or evergreen, what all forms share is their sweetly scented white flowers in summer, white or glaucous backs to their leaves, and their wetland habitat. Magnolia virginiana is a member of Section Magnolia, along with M. grandiflora and its Mexican relatives. M. grandiflora (even more widely grown but less cold tolerant) differs in its usually larger flowers, in the rufous hairs on the leaf backs, which are not glaucous, and in always being evergreen (M. virginiana may be fully or semi-evergreen, or deciduous).

This was a species well known to Native American peoples of the area. The Houma took decoctions of leaves and twigs for colds and chills, and to ‘warm the blood’, while the Rappahannock inhaled volatiles from the bark and leaves as a mild hallucinogen (Moerman 2021). Early settlers used bark extracts to treat rheumatism, coughs and colds, also steeping the fruit in spirits. The soft, aromatic, straight-grained wood is easily worked and much used for veneer and containers (Priester 1990). The species was first described scientifically from material cultivated in Europe, this apparently being the first Magnolia species grown there. By 1688 it was in the extraordinary collection of plants assembled at Fulham Palace by Henry Compton, Bishop of London, probably collected by John Bannister, whom Compton had sent to Virginia as a missionary (Treseder 1978). The type species of the genus, Linnaeus’ specific epithet of 1753 marks its place of origin.

The flowers have a sweet, fruity scent, and can make a fine sight in North American gardens. Sargent (1919) made the bold claim that ‘in all North America there is not a more delightful shrub to plant in the garden, or one that will give larger returns in beauty and fragrance’. However, in Britain’s cool, maritime climate the flowers rarely make much visual impact. They last for two days and are certainly pollinated by beetles. Bees also visit, forcing their way in to collect pollen; the extent to which they bring about pollination is contested (Thien 1974; McDaniel fide Treseder 1978; Zale 2009). In its native habitats M. virginiana flowers from June until mid-August; in the British Isles, even in southern areas, it flowers rather sporadically during August and September. Fruits are seldom seen in the British Isles but in North America they are an ornamental feature, crimson with bright red seeds.

This is a plant of moist places, where it sometimes forms a small thicket by suckering. Acer rubrum, Persea borbonia and Gordonia lasianthus are frequent companions. In gardens a sunny position on humus-rich, moist but well drained soil is ideal, although it will survive some waterlogging. Normally found on acidic soils, it tolerates lime in gardens (Treseder 1978). It ‘does quite well’ on heavy clay in Missouri (Missouri Botanical Garden 2021).

Despite its early introduction, it is not a particularly common plant in European gardens, partially eclipsed by M. grandiflora. The usual British experience is of rather weak growth; it is generally seen as a straggly shrub or small tree increasing slowly each year. A range of forms has been tried here, but none has been entirely successful – to make really strong growth Magnolia virginiana seems to need hot summers. Larger (inevitably older) specimens are recorded in some British gardens (The Tree Register 2021). Examples include a semi-evergreen tree of 9 m × 136 cm (2011) on the former Knap Hill Nursery site, Woking, Surrey; an old evergreen at Chateau la Chaire, Jersey (8 m × 67 cm, 2013); and a specimen labelled var. australis in the Valley Gardens, Windsor Great Park (8 m × 63 cm, 2021).

In continental Europe it is well represented in Belgian collections, with many cultivars grown at both Arboretum Wespelaar and Arboretum Provinciaal Domein Bokrijk (Plantcol 2021). It has been grown in Poland since the 19th century, reshooting after damage in cold winters (Anisko & Czekalski 1991), while it appears to be growable if marginal in SW Sweden (Carlsson 2006; Gothenburg Botanical Garden 2021). Cultivar selection is important in colder areas, deciduous northern forms being a safer bet.

In North America it is commonly planted within its native range, and its Zone 5 hardiness makes it useful in the lower Midwest (Dirr 2009; Missouri Botanical Garden 2021) – again, cultivar selection is important in colder areas. On the West Coast it is represented in major collections (University of Washington Botanic Gardens 2021; Hoyt Arboretum 2021; University of British Columbia 2021).

The experimental hybrids ‘Freeman’ and ‘Maryland’ confirm that M. virginiana will cross with the tetraploid M. grandiflora. Natural hybrids have been suspected where their ranges meet (Meyer 1997). Artificial hybrids include M. × thomsoniana (M. tripetala × M. virginiana).