How to grow magnolias
All you need to know about growing magnolias, in this detailed Grow Guide.
Magnolias are beautiful shrubs and ornamental trees that bring a touch of show-stopping glamour to the garden. Their sumptuous, tulip- or star-like flower colours range from pure white through pink to deep magenta and even yellow. Many also have a lovely fragrance.
Magnolias can be deciduous or evergreen, and range in size from small shrubs to large trees. Most prefer neutral or acidic soil. If you don't have the right type of soil, the smaller magnolias grow well in pots. Many flower in spring, but some flower in summer.
Magnolia trees and larger shrubs are ideal for growing as standalone trees, while the smaller magnolia trees such as Magnolia stellata look good in a border or make good trees for pots. Read more about trees for small gardens. Evergreen magnolias, such as Magnolia grandiflora, can be trained against a wall.
A magnolia bush or tree is a long-term investment – they are slow growing and can take 10-20 years to reach their ultimate size. It's therefore worth taking the time to choose the right variety for your garden. The flowers, ultimate size and the conditions in your garden will determine which magnolia you grow. If it's happy, it will thrive and reward you with a fantastic display of flowers.
How to grow magnolias
Most magnolias do best in acidic to neutral soil. If you don't have the right soil in your garden, or don't have room for a large tree, the smaller magnolias grow very well in pots. Magnolias need a sheltered spot, away from strong winds. Avoid frost pockets, as frost can damage the flowers in spring. A spot that gets plenty of sun will ensure a good display of flowers. Prune lightly in mid-summer to early autumn. Ensure the soil does not dry out in summer.
- Where to grow magnolias
- How to care for magnolias
- How to propagate magnolias
- Magnolia problem-solving
- Types of magnolia to grow
Where to plant magnolias
Magnolias grow best in fertile, well-drained, slightly acidic soil in full sun. Choose a sheltered spot that is not in a low-lying frost pocket – frost can damage the flowers. If you live in a cold part of the country, choose a variety that flowers later. Bear in mind the eventual height and spread of the tree and make sure that you have allowed room for it – some magnolias can grow very large. If you're concerned about growing a magnolia near the house, opt for a small magnolia tree. If you have alkaline soil, grow Magnolia grandiflora or Magnolia delavayi.
How to plant magnolias
Magnolias are best planted in autumn or late spring. They have shallow roots, so you don't need to dig a very deep hole. Dig a generous hole to the same depth of the pot your magnolia comes in. Avoid damaging the fleshy roots, as this can inhibit flowering. Add well-rotted garden compost or leaf mould around it, and check the level of the plant so that the point where it has been grafted is not below the soil. Gently firm in the plant with your heel and water in well. Mulch with an acidic mulch such as bark, or garden compost. Keep the plant well watered while it establishes.
More like this
In this video, Monty Don demonstrates how to plant a magnolia in a border, explaining the best way to prepare the planting hole, what type of soil it needs, and how to ensure it settles in well. He also recommends a compact variety with gorgeous dark pink flowers, ideal for a small garden:
Where to buy magnolias online
How to care for magnolias
Pruning magnolias is best done after they has flowered, to remove broken, diseased or crossing branches. Magnolias don't respond well to hard pruning and may cease flowering afterwards. So if you do have to restrict the size of your shrub or tree, or renovate it, do this over a few years, pruning only a few branches at a time to avoid stressing it. Mulch in spring with manure, composted pine bark or leaf mould. Ensure that the plant does not dry out in summer.
How to propagate magnolias
Magnolia shrubs are propagated by layering.
Magnolias can be propagated by cuttings, but they may need extra heat and light in winter. Deciduous magnolias can be propagated by taking softwood cuttings in early summer and evergreen varieties by semi-ripe cuttings in late summer and autumn.
Growing magnolias: problem solving
The most common problem when growing magnolias is a lack of flowers. Young magnolias can take several years to flower, so be patient. Make sure you have the right soil – neutral to acidic, not alkaline – and the right spot. Magnolias need plenty of sunshine and shelter from strong winds and frosts, which can damage the flowers. Heavy pruning in summer will remove the developing flower buds and will also stress the tree, preventing it from flowering. Lack of water can also stress the tree.
Blackened foliage is due to frost damage. New magnolia leaves should resprout when the weather warms.
Catherine Mansley from BBC Gardeners' World Magazine explains why magnolias may not always flower and how to encourage them to do so, in our Quick Tips video:
Magnolias rarely suffer from pests, but can be prone to a few fungal diseases.
Honey fungus can spread underground and attack and kill the roots of magnolia, eventually killing the plant. Symptoms to look out for include die-back, pale foliage, an absence of flowers, bleeding and cracking bark.
Phytophthora root rot can cause similar symptoms to honey fungus, including sparse foliage and dieback. It can be a problem on heavy or waterlogged soils.
Bracket fungus also causes dieback, as well as thinning of the tree crown. You will also spot large fungi on the branches of the trees. By the time these appears, there will have been extensive decay in the heart of the branch, which may fall off.
In all three cases, there is little you can do. You may need to dig up the plant and the surrounding soil, and replace with a different shrub or tree that is less prone to fungal problems.
Advice for buying magnoliaHere's our guide to buying a magnolia for your garden, including how to choose and where to buy:
- Magnolias are available in garden centres and nurseries, as well as specialist nurseries. Bear in mind that you will get a better selection at a specialist nursery
- Check that you have the right conditions to grow a magnolia. Most need slightly acidic soil to thrive. A good rule of thumb is to check whether magnolias are growing in front gardens in your area
- Bear in mind that your plant may take several years to flower. Many are sold on a grafted rootstock, and should flower after three to five years
- If you live in a frost pocket or in the north of the UK, choose a variety that flowers in late April or May, to avoid frost damage to the buds. Varieties include 'Caerhays Surprise' and 'Apollo'
- Research the ultimate height and spread of your magnolia. Although they are slow growing, taking 10 or even 20 years to reach their ultimate height, you need to bear this in mind when buying
- Buy as mature a plant as you can afford – it will establish better. Add plenty of organic matter when planting and do not let the plant dry out in summer
Where to buy magnolia online
Magnolia varieties to grow
Best magnolia for a small garden or pot
Magnolia stellata is a great small magnolia tree for a smaller garden or a container, in sun or shade. It's a deciduous shrub with star-shaped blooms that appear before the leaves, in early spring. They have a very light fragrance. There are several varieties to choose from, including the white-flowered Magnolia stellata 'Centennial' and the pale pink Magnolia stellata 'Jane Platt'.
Height x spread: 3m x 3m
Magnolia x soulangeana ‘Alexandrina’ has goblet-shaped, pink flowers that are darker at the base than at the tips of the petals. It remains a manageable shrub size for many years.
H x S: 6m x 6m
Magnolias for medium-sized gardens
Magnolia 'Apollo’ has huge, dark pink flowers that fade once open to pale pink and white. It forms an open, spreading, often multi-stemmed small tree.
H x S: 5m x 5m
Magnolia x loebneri ‘Leonard Messel’ bears pale pink, goblet-shaped flowers that become more star-shaped as they open. It remains a manageable size for many years.
H x S: 8m x 6m
Magnolias for large gardens
Magnolia sieboldii or the Chinese magnolia is a very hardy, deciduous species. The scented flowers are cup-shaped and large with deep maroon centres. They have a long flowering season from May to September and the foliage is attractive and glossy. A real statement tree.
H x S: 6m x 8m
Magnolia × brooklynensis ‘Woodsman’ is an unusual magnolia, with multicoloured spring flowers in pink, white and green.
H x S: 10m x 6m
Best magnolias for alkaline or chalky soil
Magnolia grandiflora is a large evergreen that produces large white, lemon-scented flowers in August and September. An impressive, stately plant, it can be grown against a sunny wall, where it will appreciate the heat. It tolerates more alkaline and chalky soils. It can eventually grow very large. H x S: 15m x 15m.
Magnolia ‘Goldfinch’ has unusual yellow flowers in late spring. H x S: 10m x 10m.
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