Magnolia grandiflora ‘St Mary’ – St Mary Magnolia

Name: Magnolia grandiflora ‘St Mary’ – St Mary Magnolia
Brand: Evergreen Trees Direct
Price: 620.00 AUD
Availability: InStock

$620.00

Tax included. Shipping calculated at checkout.

999 in stock

Size: 100L

100L

Current Stock Height Guides

100L: Enquire within for height guide information.

Trade Customers

We supply advanced trees to landscapers, developers, architects, and councils Australia-wide. Trade clients receive fast quotes, expert advice, and access to premium stock with reliable freight.

About Magnolia grandiflora ‘St Mary’ – St Mary Magnolia

Magnolia grandiflora ‘St Mary’ is a compact evergreen form of the Southern Magnolia, selected for its dense habit and large, showy flowers. The foliage is glossy and dark green on the upper surface with a contrasting bronze-brown underside, providing year-round interest. From late spring through summer, it produces large, creamy-white, cup-shaped flowers up to 25 cm wide, each with a rich fragrance. Mature specimens generally reach 5–8 metres in height and 3–5 metres in width, with a broadly pyramidal crown.

This cultivar has a moderate growth rate and is hardy once established. It thrives in full sun to part shade and prefers slightly acidic, well-drained soils. Magnolia grandiflora ‘St Mary’ is frost tolerant, evergreen, and low-maintenance, requiring only occasional pruning to maintain form. Once established, it shows good drought tolerance, making it adaptable to a variety of garden and landscape situations.

They look excellent when planted as specimen feature trees, used as screening in larger gardens, or incorporated into civic landscapes where year-round foliage and summer flowering are desirable. Their upright, pyramidal form also makes them suitable for avenue planting or as statement trees in formal gardens.

Key Information to Know

Evergreen / Deciduous

Magnolia grandiflora ‘St Mary’ – St Mary Magnolia is an Evergreen (foliage year round) Tree

Mature Height & Width

Mature Height: 5–8 metres

Mature Width: 3–5 metres

Magnolia grandiflora ‘St Mary’ – St Mary Magnolia is expected to grow 20 – 40 cm per year (moderate).

Frost Tolerance

Is Magnolia grandiflora ‘St Mary’ – St Mary Magnolia frost tolerant?

Magnolia grandiflora ‘St Mary’ – St Mary Magnolia is Frost Tolerant – Can handle light to moderate frost once established.

Flowering Information

Magnolia grandiflora ‘St Mary’ produces large, creamy-white, lemon-scented flowers from late spring into summer, with intermittent blooms continuing into early autumn. These bold, upright blooms contrast beautifully with the glossy green foliage and rich bronze undersides, creating a classic and highly ornamental magnolia display.

Native Information

Is Magnolia grandiflora ‘St Mary’ – St Mary Magnolia an Australian Native? No

Magnolia grandiflora ‘St Mary’ – St Mary Magnolia is Native to Southeastern United States, where Magnolia grandiflora grows naturally in coastal plains and moist woodlands.

Wildlife Value

Its nectar-rich flowers attract bees, beetles and other pollinating insects, while the dense evergreen canopy provides excellent nesting and shelter for small birds. The seed-bearing cones that follow offer food for wildlife and contribute to improved biodiversity in ornamental garden settings.

Sunlight Information

Magnolia grandiflora ‘St Mary’ – St Mary Magnolia will thrive best in:

Full Sun
Part Shade

Preffered Soil

Magnolia grandiflora ‘St Mary’ performs best in well-drained, slightly acidic loam or sandy loam soils. It may struggle in heavy clay, alkaline or poorly drained areas unless improved with organic matter and coarse material to enhance soil structure and drainage. Keep soil evenly moist during establishment, then maintain deep, occasional watering as the tree matures to support dense evergreen growth, healthy roots and consistent seasonal flowering.

Botanical Information

Common Name: St Mary Magnolia

Genus: Magnolia

Botanical Species: Magnolia grandiflora

Family: Magnoliaceae

Botanical Name: Magnolia grandiflora ‘St Mary’

Landscape Uses

Screening or Privacy
Feature Tree
Avenue Planting
Shade Tree
Council or Civic Landscapes

Magnolia grandiflora ‘St Mary’ – St Mary Magnolia works in an:

Formal Garden – structured, symmetrical design with clipped shapes.
Modern Garden – sleek, minimal, and design-led planting.
Cottage Garden – romantic mix of flowers, colour, and texture.
Low-maintenance Garden – resilient choices for easy care and year-round appeal.

Planting, Spacing & Care

Select a sunny to partly shaded site with free-draining soil.
Dig a hole twice as wide as the root ball.
Backfill with improved soil enriched with organic compost.
Water thoroughly after planting and mulch to conserve moisture.
Stake young trees if planted in exposed sites until roots are established.

Hedging & Screening: Space 2 – 3 m apart (when clipped for screening)
Feature Planting: Space 3 – 5 m apart
Shade Canopy: Space 4 – 6 m apart
Avenue Planting: Space 4 – 6 m apart

Water regularly until established; reduce as it matures.
Fertilise annually in spring with a balanced fertiliser for flowering trees.
Prune lightly after flowering to maintain form and density.

Sandy soils: Requires additional organic matter and mulching to conserve moisture.
Loamy soils: Ideal growth and best flowering performance.
Clay soils: Performs in light clay with improved drainage.
Coastal soils: Suitable in sheltered coastal gardens away from salt spray.
Poor soils: Benefits from compost and balanced fertiliser.

Magnolia grandiflora ‘St Mary’ – St Mary Magnolia is expected to grow 20 – 40 cm per year (moderate).

Medium Growth Rate

Root Ball Dimensions (Width × Depth) For Planting

Use this as a reference when digging your planting hole. We recommend digging at least 10% wider than the dimensions below to encourage strong root development.

30cm Pot: 33cm (W) × 30cm (D)
40cm/45L Pot: 44cm (W) × 41.5cm (D)
50cm Pot / 70L Pot: 55cm (W) × 41.8cm (D)
100L Bag: 50.6cm (W) × 52.8cm (D)
150L Bag: 66cm (W) × 55cm (D)
200L Bag: 71.5cm (W) × 60.5cm (D)
300L Bag: 88cm (W) × 63.8cm (D)
400L Bag: 99cm (W) × 66cm (D)
500L Bag: 122cm (W) × 66cm (D)
750L Bag: 134cm (W) × 69cm (D)
1000L Bag: 146.3cm (W) × 71.5cm (D)
2000L Bag: 176cm (W) × 82.5cm (D)

Ideal Conditions

Subtropical QLD (Brisbane, Gold Coast, Sunshine Coast)
Inland QLD (Darling Downs, Central QLD)
Northern NSW (Byron, Coffs, Armidale)
Sydney & Central Coast
South Coast NSW (Illawarra to Bega)
Inland NSW / Tablelands (Orange, Bathurst, Canberra)
Melbourne & Surrounds (Metro, Bayside, Geelong, Bellarine, Mornington)
Western District & Central VIC (Ballarat, Bendigo, Hamilton)
Gippsland (Latrobe Valley, East Gippsland)
Adelaide Metro & Coastal
Adelaide Hills & Barossa

Thrives in

Full Sun
Part Shade

Frost Tolerance

Frost Tolerant – Can handle light to moderate frost once established.

Drought Tolerance

As a young tree it requires regular watering, but once established ‘St Mary’ develops good drought tolerance. It performs strongly in warm, dry and coastal conditions and maintains its dense, upright structure with deep, occasional watering during extended dry spells.