Feeding magnolias: when, how & the best magnolia feed

Sabine
Sabine
Sabine
Sabine

I am currently studying agricultural and food economics. As a keen hobby gardener, plants take up most of my free time. A few years ago, I got especially interested in herbs, which is why I completed my studies to become a certified herbalist in 2018.

Favourite fruit: apples, cherries
Favourite vegetables: potatoes, fennel

Feeding magnolias is an essential part of getting your magnolia trees to bloom beautifully. Read all about what to bear in mind when fertilising magnolia trees and find out which type of magnolia feed is best.

Many healthy magnolia flowers
Only happy and healthy magnolias will flower so abundantly [Photo: nnattalli/ Shutterstock.com]

Each spring we are blessed by richly flowering magnolias (Magnolia). But magnolias have a relatively high demand for nutrients. So, in order for your magnolia to flourish and bloom to its fullest potential, you need to provide it with enough water and nutrients. That said, these trees need fertilising according to the stage of development they are in. Where you plant your magnolia can also greatly influence its growth. Keep reading to learn all about feeding magnolias and where is best to plant them.

Planting and feeding magnolias: when and how

The best time to plant magnolias is in autumn around October or November, when the plant is dormant. However, in harsher locations, it is better to plant them in spring, by April at the latest. Depending on the species and variety, magnolias prefer a sunny to semi-shady and sheltered spot. They need humus-rich, nutrient-rich and slightly acidic soil with a pH value of about 5.5 to 6.8. With a few exceptions, magnolias do not generally tolerate calcareous, alkaline soils. When choosing somewhere to plant your magnolia, ensure there is enough space between it and any surrounding trees and shrubs. Solitary magnolia trees will require around 4 to 8m metres (diameter) of space. Soils that are too sandy are just as unsuitable for magnolias as those that are too loamy. To give your magnolia tree the best start, dig a sufficiently large planting hole and mix the excavated soil with rhododendron soil.

Magnolias grown with bark mulch
A layer of bark mulch prevents the soil around your magnolia tree from drying out [Photo: andysartworks/ Shutterstock.com]

Fertilise magnolia trees every year in spring, around March or April, with compost. To do this, simply apply a thick layer of compost around the base of the tree and the root plate, and lightly work it in. Be especially careful not to damage the shallow roots just below the soil surface. If you do not have your own compost, you can also use a magnolia feed from a specialist shop. The best fertilisers for magnolia trees are organic, slow-release fertilisers, such as our Plantura All Purpose Plant Food for instance. Our granular fertiliser contains a high proportion of organic matter and gradually releases nutrients to your plants over a period of 3 months. It is also particularly gentle on plants and soil and poses no threat to animals in the garden.

All Purpose Plant Food, 1.5kg
All Purpose Plant Food, 1.5kg
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(4.8/5)
  • Perfect for a variety of plants in the garden & on the balcony
  • Promotes healthy plant growth & an active soil life
  • Long-lasting fertiliser that is free from animal products - child & pet friendly
£9.99

From this point on, potted magnolias will need feeding once a fortnight. Rhododendron or bog bed fertiliser, for example, is well-suited to this. There is no need to feed magnolias planted in the ground additionally, unless you notice any symptoms of nutrient deficiencies on the leaves. That said, you can feed your magnolia 3 to 4 weeks before they flower or spread some rhododendron soil on the root plate to give them a bit of a boost. If you decide to do this, take the different flowering times of the individual species into account. While tulip magnolias (Magnolia x soulangeana) flower as early as April, evergreen magnolias (Magnolia grandiflora) and summer magnolias (Magnolia sieboldii) usually take until May or June. Adding a layer of mulch also ensures that the soil does not dry out during the summer months. To help your magnolia survive the winter, apply more compost in autumn.

How and when to plant and feed magnolias

  • Improve the soil with rhododendron soil
  • Fertilise in March/April with compost or an organic slow-release fertiliser
  • If necessary, fertilise a second time before flowering
  • Apply a layer of mulch to help lock in moisture throughout the summer
  • Final application of compost in autumn

Different types of fertilisers

There are many fertilisers for magnolias for you to choose from. In addition to organic fertilisers, there are also various mineral fertilisers available for you to buy. Some resourceful gardeners even fertilise their magnolias with coffee grounds. Keep reading to learn about some of the advantages and disadvantages of the individual methods.

Fertilising magnolia trees with organic fertilisers

Especially with magnolias, you should make sure that you use fertilisers that lower the pH value or, at the very least, do not increase it. In addition to compost, horse manure or bone meal are also ideal for fertilising magnolias trees. It is best to sprinkle the bone meal on the root plate and then cover it with an 8cm-thick layer of mulch. Over time, this will decompose and release additional nutrients to the magnolia tree. The mulch ensures that the soil stays moist throughout the summer months. It also protects the cold-sensitive magnolia from frost during the winter.

If you do not have access to natural fertilisers, you can also find suitable products in specialist shops. Organic fertilisers may not work as quickly, but they are the more sustainable choice in the long term and have many advantages:

  • Organic fertilisers are slowly broken down by microorganisms in the soil and gradually release nutrients to the plant over a longer period of time.
  • They promote healthy soil life, which is good for microorganisms, earthworms, etc.
  • They are much better for our environment, as they do not contain harmful chemicals
Close up of horse manure
Horse manure is an example of a suitable natural fertiliser [Photo: Valerii Ivashchenko/ Shutterstock.com]

To ensure that you provide your magnolia with the ideal amount of nutrients, follow the step-by-step instructions below.

How to apply an organic slow release fertiliser

Our Plantura All Purpose Plant Food is an organic fertiliser that is suitable for all plants that do not have a particularly high potassium requirement, making it ideal for feeding magnolias. It consists exclusively of plant residues from the food and animal feed industries and is therefore free of any animal products. Our granular fertiliser is quick and easy to apply and provides your magnolia trees with nutrients for 3 months. Simply sprinkle some on the root plate and water well. There is no need to manually work our feed into the soil.

  1. Before planting, work 100 – 150 g/m² (8 – 12 tablespoons) of our Plantura All Purpose Plant Food into the soil.
  2. Water the soil and the freshly planted magnolia well to dissolve the granules.
  3. Every year in spring, apply about 80 – 120 g/m² (6 – 10 tablespoons) to the root disc and water.
  4. Applying a small amount of fertiliser about 3 – 4 weeks before your magnolia is due to flower will help it to bloom beautifully.
All Purpose Plant Food, 1.5kg
All Purpose Plant Food, 1.5kg
star-placeholder star-placeholder star-placeholder star-placeholder star-placeholder
star-rating star-rating star-rating star-rating star-rating
(4.8/5)
  • Perfect for a variety of plants in the garden & on the balcony
  • Promotes healthy plant growth & an active soil life
  • Long-lasting fertiliser that is free from animal products - child & pet friendly
£9.99

Feeding magnolias with mineral fertiliser

In addition to using organic fertilisers, feeding magnolias with mineral fertilisers is also possible. These provide a quick boost of nutrients, but if used incorrectly there is an increased risk of over-fertilisation. High concentrations of nutrient salts in the soil can not only damage the sensitive roots of magnolias, but can also leach into the groundwater. In contrast, organic fertilisers do not work as quickly, but they do help to improve soil health. Moreover, as organic fertilisers are slowly broken down by microorganisms in the soil, there is little to no risk of overdosing.

Fertiliser spray cannister next to garden
When choosing a fertiliser for magnolias, it is important to weigh the advantages and disadvantages of each type [Photo: Sergey Kamshylin/ Shutterstock.com]

Feeding magnolias with coffee grounds

Whilst it may sound odd, you can also use coffee as a fertiliser for feeding magnolias. Strictly speaking, you use the coffee grounds for this, which should ideally have been dried beforehand. This prevents mould from growing during storage. Coffee grounds are often thrown away, but they still contain many nutrients that are important for plants, such as nitrogen, phosphorus and potassium. Organic materials also attract useful soil organisms, such as earthworms, and promote humus formation in the soil. Coffee grounds are also a naturally-occurring acidic fertiliser that can lower the pH value in the soil, making it especially well-suited fertilising magnolia trees. Simply sprinkle small amounts of it on the root plate from time to time and work it in carefully on the surface.

What to use to fertilise your magnolia trees:

  • Natural options: compost, horse manure, bone meal or a long-lasting organic fertiliser
  • Mineral fertiliser: danger of over-fertilisation
  • Home remedies: coffee grounds
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