Deciduous Magnolias
Flowering on bare branches during late Winter and early Spring, deciduous magnolias are one of the highlights of the colder months. Whilst most of us are familiar with the purplish white, saucer-shaped flowers of the traditional Magnolia soulangeana in large old gardens around Melbourne, there are now many new varieties available, several of which are suitable for growing in smaller spaces, including pots. Colours range from pure white through shades of pink and purple, to almost black, and there are even some beautiful yellow flowering varieties.
Growing deciduous Magnolias
Magnolias grow best in a sunny position with shelter from strong wind, as this can damage the flowers. They prefer a fertile, neutral to slightly acid soil that is moist but well-drained. Feed magnolias with a complete fertiliser such as Growbetter All Purpose Fertiliser in Spring and late Summer and keep trees well mulched and watered, especially during the first few years of establishment.
If growing a magnolia in a pot, choose a compact/dwarf variety and ideally plant in a pot at least 50cm in diameter. Use premium quality potting mix and take care that it does not dry out, especially during Summer. Deciduous magnolias grow naturally into a well-shaped tree and rarely require pruning, except to remove weak, crossing, diseased or damaged wood.
Deciduous Magnolia varieties for medium to large gardens
There are many different species and hybrids of magnolia, with heights ranging from 3m to 6m plus. Magnolias are quite slow growing and, even when grown in ideal conditions, will not usually achieve the size stated on the label for at least 10 years or more.
Magnolia denudata (Yulan magnolia) – Probably the most popular of all the white flowering magnolias, this has ivory white, goblet shaped flowers with a subtle lemon fragrance.
Magnolia soulangeana (Saucer magnolia) – An old favourite, this has traditional tulip-shaped white flowers with varying degrees of purple blush. Popular cultivars include ‘Alba Superba’, ‘Burgundy Glow’ and ‘San Jose’.
Magnolia x ‘Heaven Scent’ – A vigorous grower, with strong, upright branches. Heaven Scent is a prolific bloomer, with lightly fragrant, pale lavender-pink flowers that are lighter at the tips and white on the inside.
Magnolia x ‘Vulcan’ – An extremely popular New Zealand-bred hybrid that flowers at a young age. Large, deep magenta flowers can take a few years to develop their strong colour.
Magnolia x ‘Black Tulip’ – Another New Zealand-bred hybrid, Black Tulip has a narrow habit that makes it suitable for restricted spaces. The tight goblet-shaped flowers open dark purple-red and fade slightly as they age. Like Vulcan, it can take a few years for the colour to fully develop.
Magnolia x ‘Elizabeth’ – A strong grower that can reach 6m + in height, making it a perfect feature tree for a large lawn. Flowers are a beautiful primrose yellow, the colour intensity of which can vary from one year to the next.
Deciduous Magnolias for small gardens and planters
Compact and dwarf varieties usually have a maximum height of 3m, which makes them well suited to growing in pots, courtyards and small gardens.
Magnolia stellata (Star magnolia) – Grown either as a large, multi-stemmed shrub, or small tree, Star magnolias produce masses of large, star-like white or pink flowers in early Spring, and their leaves usually turn a deep golden colour in Autumn.
Magnolia liliiflora 'Nigra' (Purple Lily magnolia) - usually grown as a multi-stemmed shrub, Nigra has fragrant, tulip-shaped flowers that are deep purple on the outside and creamy-white on the inside.
Magnolia x ‘Genie’ – One of the darkest magnolias, New Zealand-bred Genie is also one of the most compact. It has very dark purple buds opening to deep burgundy goblet-shaped flowers in late Winter/early Spring and, unlike other magnolias, will flower again in Autumn.
Magnolia x ‘Cameo’ – Another very compact, free-flowering variety from New Zealand, Cameo has striking two-toned flowers that are reddish-purple on the outside and white-blush pink on the inside.
Pest and diseases
Deciduous Magnolias have very few pests, but slugs and snails may attack the foliage, and flower buds are attractive to possums. Magnolias can be susceptible to scale, especially when stressed. You can treat scale with a horticultural oil, but the best defence is to improve the health of the tree. Magnolias are rarely troubled by diseases, although leaf spot can occur as a result of a wet Spring. Whilst a copper fungicide spray can be applied as a preventative measure during mid-Winter, it is often sufficient to simply remove the worst affected leaves.
