IN THIS GUIDE
You might think of Magnolias as a plant for larger gardens, but some Magnolias can be grown in pots.
In this article, we will talk about which magnolias to grow in pots in a container garden, and the choices you will have to make to keep them healthy and happy.
Can You Grow Magnolia In Pots?
In short – yes!
If you grow magnolia trees in the ground, you will obviously be able to choose from a wider variety of plants, and they will take a lot less work.
Container gardens are generally higher maintenance for the gardener.
However, there is one very good reason why you might wish to grow Magnolia in containers, and that is because of their pH requirements.
Magnolia trees like neutral or acidic soil conditions.
While some can cope with more alkaline conditions, if you have very alkaline soil, it is often best to grow Magnolias in containers rather than fighting to amend the pH and grow them in the ground.
Fortunately, magnolia trees have rather shallow roots, which can make them a good candidate for growing in larger containers.
Some types have fragrant flowers which makes them great for positioning in pots close to a seating area or outdoor leisure space.
Potted Magnolia Varieties
Magnolia trees can be full-sized trees or larger shrubs.
If you plan on growing Magnolia in a container then it is important to choose the right variety.
Those with smaller forms and less vigorous growth habits are generally easier to grow in pots.
Some options to consider which can be good for container gardening include:
- Magnolia ‘George Henry Kern’
- Magnolia ‘Susan’
- Magnolia stellata ‘Jane Platt’
- Magnolia stellata ‘King Rose’
- Magnolia stellata ‘Royal Star’
- Magnolia stellata ‘Rosea’
- Magnolia denudata ‘Sunrise’
- Magnolia denudata ‘Yellow River’
- Magnolia x loebneri ‘Mag’s Pirouette’
- Magnolia x loebneri ‘Merrill’
Make sure that you understand how large the Magnolia you are considering will eventually grow, and remember that while some Magnolias can be grown in containers, not all can.
Even those which are good for container growing will need a sizeable pot and the right conditions to thrive.
Positioning Potted Magnolia
Magnolias, whether grown in the ground in a garden or in pots, will require a site that is as sunny and sheltered as possible.
Magnolias are actually usually pretty hardy in the UK, however, the flowers of magnolias can easily be damaged by early spring frosts.
Frost can also damage evergreen foliage in the autumn months.
Choosing Containers For Magnolia
Magnolias are usually purchased as pot grown trees, though they can come in a range of containers of different sizes.
It is best to repot your Magnolia as soon as it arrives into larger, heavy containers which can support the weight of a small tree or shrub and which will not tip over easily.
You can purchase containers, but there is also a range of reclaimed items you could consider.
Remember to choose a container that will not dry out too quickly during the summer months.
Inadequate water over the summer is one of the common reasons why a magnolia might not flower as expected.
Remember that a black or dark coloured container will heat up and dry out more quickly.
The material from which a container is made is also important – glazed pots are better than terracotta for water retention, for example.
It is also important to make sure that your container has drainage holes and allows for good drainage too.
Magnolia trees grow root systems very quickly and intricately, so it is important to choose a container that will suit the ultimate size of your tree.
Look at the girth of the trunk to get an idea of how wide the container needs to be.
A Magnolia with a trunk that is 2cm wide, you will need a container at least 60cm wide and 60cm tall.
For each centimetre around the diameter of the trunk, the container should be 30cm wider and taller.
So if a mature magnolia tree trunk is 5cm around, it will need a container or planter 1.5m wide and 1.5m tall.
Larger containers will be needed to grow Magnolia to maturity in pots.
Potting Mix For Magnolia
As mentioned above, Magnolias can thrive in neutral or acidic soils.
Many magnolias will grow perfectly well in a general multi-purpose compost with added John Innes (or a homemade equivalent).
However, certain varieties will thrive in more acidic conditions and so it can sometimes be beneficial to fill your pots for Magnolia with an ericaceous potting mix.
Whichever potting mix you choose, make sure it is light and free-draining, yet moisture retentive, to keep your magnolia tree as healthy and happy as possible.
Planting Magnolia In Pots
When you are planting a magnolia into its new pot or container, it is important to take care not to damage the root system as you do so.
As is usual with trees and shrubs, it is important to make sure that you bury the magnolia to the same level that it was at in its previous pot.
Make sure the graft point is not below the surface of the growing medium.
After planting, water well around the base of the plant, and top the growing medium in the container with a leaf mould or another good quality organic mulch.
This will help to retain water in your pot and stop weeds from growing up as much around the base of your tree.
Of course, it will also help add fertility, providing nutrients as the materials decompose slowly over time.
Caring For Potted Magnolia
Remember that a magnolia grown in a container will need to be watered more frequently in dry weather than one which is grown in the ground.
Keep the soil moist throughout the summer months to keep magnolias healthy and flowering well.
Magnolias grown in the ground will typically require only mulch, and will not need additional feeding.
When grown in pots, however, some additional liquid feed may be helpful.
Feeding magnolias grown in containers in early spring with a high phosphorus and potassium liquid feed can promote healthy growth and encourage more abundant flowering.
Magnolias should only be pruned lightly, and after flowering.
Remove any branches which are dead, damaged or diseased and any which are crossed and rubbing against one another.
You can also prune to restrict size somewhat, but should be circumspect as these trees do not like or respond well to hard pruning.
If you prune too much, flowering may be reduced or cease the following year.
As long as you choose the right magnolias, place them in the right containers, with the right potting mix, in the right location, growing magnolia in pots is not too much of a challenge.
Just make sure you do not let them dry out.
Replenish mulch to add fertility each year, and your magnolia tree should be content in your container garden for many years to come.
A permaculture garden designer, sustainability consultant and freelance writer, Elizabeth works as an advocate for positive change. She aims to inspire others to reconnect with nature and live in a more eco-friendly way. She also tries to practice what she preaches as she tends her own forest garden, polyculture beds and polytunnel. See her personal website here.