Star magnolia

Sun

Full sun to partial shade; afternoon shade is helpful in hot climates. Choose a sheltered position away from frost pockets and drying winds.

Water

Keep the soil evenly moist but not waterlogged. Water deeply during dry spells, especially during the first two growing seasons.

Soil

Humus-rich, well-drained soil, preferably slightly acidic to neutral. Avoid waterlogged ground and very chalky or strongly alkaline soil.

Height

10-20 ft (3-6 m)

Spread

10-15 ft (3-4.5 m)

Flowers

Late winter to early spring, before the leaves emerge; usually white flowers with numerous narrow petals. Some selections have pink buds or pale pink flowers.

Foliage

Oval green leaves turn yellow to brown in autumn; autumn colour is variable.

Growth

Slow, often around 6-12 in (15-30 cm) a year once established.

Care needed

Low

• Plant with the root flare at soil level; choose the position carefully because established magnolias dislike being moved.
• Water deeply during dry weather rather than giving frequent light sprinklings.
• Apply 2-3 in (5-8 cm) of organic mulch each spring, keeping it clear of the stems.
• Feed lightly in spring only if growth is poor or a soil test indicates a deficiency; avoid heavy nitrogen feeding.
• Keep grass away from the root area and avoid digging around its shallow roots.

Pruning. Prune only when necessary, just after flowering, removing dead, damaged or crossing branches. Keep cuts small and retain the natural branching shape rather than clipping or cutting back hard.

Autumn

Plant while the soil is workable, or wait until spring in very cold regions; water thoroughly after planting.

Late winter

Watch developing flower buds during cold spells; cover a small plant with horticultural fleece overnight if a damaging frost is forecast.

Spring

Refresh the mulch and check that soil beneath it is moist.

Late spring

After flowering, remove damaged or crossing branches only if needed.

Summer

Water deeply during prolonged dry weather, particularly around young plants.

Late autumn

Check that winter rain drains freely and that mulch is not piled against the stems.

• Use as a specimen in a small lawn, with a broad mulched area protecting the shallow roots.
• Place beside a path or patio where the early flowers and light fragrance can be appreciated, allowing space for the mature canopy.
• Plant at a woodland edge with hellebores, ferns and other shade-tolerant groundcover.
• Set against a dark evergreen backdrop to make the white flowers stand out.

Garden styles it suits: Japanese, Woodland, English country, Modern courtyard, White garden and Small-space.

Plant it with: Hellebores, Snowdrops, Japanese painted fern, Epimediums, Camellias and Japanese forest grass.

Wildlife: Flowers provide pollen for visiting insects, including beetles and some bees. The branching canopy offers shelter for small birds.

• Late frost can turn open flowers brown. Choose a sheltered site outside a frost pocket; fleece can protect small plants, but damaged flowers will not recover.
• Scale insects can cause sticky honeydew and sooty mould. Inspect stems, remove small infestations by hand and, if needed, use a locally approved horticultural oil at the labelled time.
• Waterlogged soil can cause root rot and dieback. Improve drainage before planting, avoid overwatering and seek advice if decline continues.
• Yellow leaves with greener veins can indicate iron deficiency in alkaline soil. Check soil pH, mulch with organic matter and use chelated iron suitable for your soil if needed.

Not known to be toxic to cats, dogs, horses or people. No part is generally recognised as poisonous, but it should not be treated as food; eating plant material can still cause stomach upset.

• Loebner magnolia (Magnolia × loebneri)

  This hybrid of star magnolia and Kobus magnolia also has many-petalled flowers, but usually develops into a larger small tree. Cultivars overlap in appearance, so a reliable label may be needed.

• Kobus magnolia (Magnolia kobus)

  Usually becomes a much larger tree and has flowers with about six broad white petal-like segments, rather than the many narrow segments of star magnolia.

• Saucer magnolia (Magnolia × soulangeana)

  Has larger, cup- or goblet-shaped flowers with broad petals, commonly pink-purple outside and white inside, rather than open, many-petalled stars.

Magnolia honours the French botanist Pierre Magnol, while stellata means starry or star-shaped, referring to the flowers.

Propagation. Sow fresh seed after removing its fleshy outer coating and providing a period of moist cold conditions; germination can be slow and uneven. Seedlings may differ from the parent. Named cultivars are usually propagated by softwood cuttings, layering or grafting, with cuttings sometimes difficult to root.

Accepted botanical name

Magnolia stellata

In the US and Canada

Introduced in the lower 48 states.

Native range

Japan.

Measured

Soil pH 5 to 6.2. Average height 450 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.