In principle, magnolias are quite easy to care for, as long as they are in the right location and in the right soil. Regular fertilization is only necessary if deficiency symptoms become noticeable.
How should you properly fertilize a magnolia?
For magnolias, fertilization with mature compost in spring and autumn is suitable to cover the nutrient requirements. Potted magnolias need liquid fertilizer every two weeks, ideally a rhododendron or ericaceous bed fertilizer. If there are deficiency symptoms, targeted fertilization measures are necessary.
The right soil for magnolias
Magnolias can be real divas: If they don't feel well, they show it very clearly and simply refuse to bloom. In order to avoid giving your magnolia a reason for this kind of bickering, it's best to ensure optimal conditions when planting. In addition to the right location, this also requires a humus-rich, slightly acidic soil. Sandy soils are unsuitable for magnolias, while you should enrich loamy soil with plenty of rhododendron soil before planting.
Maintain acidic soils
If your magnolia has been in acidic soil for a few years but is ailing, these two main reasons are possible: Acidic soils usually contain little magnesium, which has also been used up after a certain period of standing. In this case, fertilize your magnolia with a fertilizer containing magnesium. Please note, however, that most commercially available ready-made fertilizers contain little or no of this mineral. However, applying an Epsom s alt solution can help, although you can also use it as a preventive measure. Furthermore, a previously acidic soil can change its pH value unnoticed. In this case, generously spreading ericaceous soil in the root area helps.
For he althy magnolias, mature compost is sufficient
He althy magnolias are provided with a thick layer of ripe (i.e. well-rotted) compost (€41.00 at Amazon) in both spring and autumn. When working in the root area, be careful not to work too deep due to the shallow roots. Adding compost in autumn should help your magnolia tree survive the winter more easily. Further fertilization (e.g. with ready-made or liquid fertilizers) is not necessary for magnolias planted in the garden. Potted magnolias, on the other hand, require regular fertilization about every two weeks with a good liquid fertilizer. A rhododendron or ericaceous bed fertilizer is also ideal here.
Recognize and counteract deficiencies
In the following overview you can at a glance assign the abnormalities you notice in your magnolia tree to the corresponding deficiency symptoms and act correctly. However, you can't go wrong if you supply your ailing magnolia with rhododendron or ericaceous bed fertilizer. This has been specially developed for the needs of plants growing on acidic soils.
| Abnormalities | What's missing? | Countermeasures |
|---|---|---|
| Leaves turn light green | Nitrogen | Fertilization with nitrogen-containing fertilizer (e.g. yellow grain) |
| Leaves turn yellow-green | Magnesium | Fertilization with Epsom s alt solution |
| Leaves develop necrosis between the leaf blades (i.e. brown or black spots) | Magnesium | Fertilization with Epsom s alt solution |
| Leaves turn brown from the edge of the leaf | Potassium | Fertilization with Thomaspotash |
| Leaves turn yellow | Potassium | Fertilization with Thomaspotash |
| Leaves turn blue-gray | Phosphorus | Fertilization with Thomaspotash |
| Leaves turn yellow | Iron | Fertilization with iron fertilizer |
| Pale leaves with strong green leaf veins | Iron | Fertilization with iron fertilizer |
Tips & Tricks
Magnolias do not have a particularly high nutrient requirement and are therefore at risk from possible over-fertilization. It's better to pay close attention to the leaf color and flowering behavior of your magnolia tree, then you can quickly compensate for existing nutrient requirements.