Magnolia Tree Diseases: Little Gem Magnolia Common Problems and Solutions

Diseases That Infect Magnolia Trees

The magnolia tree can become infected by a number of diseases as mentioned below. However, you can ensure that your Little Gem Magnolia remains healthy and beautiful for several years by following proper disease prevention methods discussed below.

Magnolia Tree Disease Root Rot

1. Root rot is caused by over-watering or poor soil drainage. It is important to plant Magnolia in well-drained soil. You may add river sand or perlite in the soil to make it free-draining.
2. Water your magnolia only when the top 2-3 inches of soil is dry.
3. If root rot is already present, the tree may need to be relocated in new soil.

Magnolia Winter Burn

A the magnolia tree is not cold-hardy, it can suffer from winter burn, causing browning of the leaves, if it is exposed to harsh winter winds.  To avoid winter burn, it is best to plant your magnolia in a sheltered location.

Magnolia Disease Brown Leaf

Iron Chlorosis in Little Gem Magnolia

If the magnolia is affected due to iron chlorosis problem, then the leaves turn yellow due to a lack of iron in the soil. This happens if the soil is too alkaline, which makes it difficult for the tree to absorb iron. To solve this problem, you can amend the soil with sulphur to lower the pH or use chelated iron fertilizers.

Insects and Pests on Magnolia Tree

Aphids on Magnolia Trees

Aphids feed on the sap of the magnolia tree, they suck the fluids from the stems and leaves, causing yellowing of the leaves and reducing its growth. To control aphids, you can use insecticidal soap or flush them off with a stream of water from a hose.

Scale Insects on Magnolia Tree

Scale insects attach themselves to the stems and leaves of the magnolia tree, feeding on its sap, reducing the plant's vigour, resulting in yellowing of the leaves and reduced growth and less flowers. However, even heavy scale insects infestation will not kill the magnolia tree. To control scale insects, you can use horticultural oils or insecticidal soap.

Magnolia Disease Borer

The larvae of the tiny beetles bore into the tree’s wood of young magnolia tree and continue eating the plant down to the root structure. The borer is identified as a spongy appearance where they entered the tree. If not treated in time, the plant may die.

You should prune off the infected portion of the tree. You can also use a spray of horticultural or pest oil. 

Fungal Diseases on Magnolia Trees

Powdery Mildew on Magnolia Trees

Powdery mildew is a fungal disease that causes white dusty spots on the foliage and stems. It rarely will kill your magnolia tree, remove it with a jet of water or insecticidal soap.

Anthracnose Diseases on Magnolia Trees

Fungal disease like anthracnose spreads due to wet and windy weather conditions. Although they rarely kill your magnolia tree but certainly it will weaken the tree and also produce an unsightly black spotty foliage appearance.

Magnolia Leaf Spots

The fundal disease on magnolia causes leaf spots. At the beginning of disease you will notice tiny black or purplish/brown spots on the leaves. Remove and destroy the diseased leaves from the tree. Increasing ventilation in the foliage and a fungicide spray may solve the problem.

How To Prevent Problems on Magnolia Trees

The best way to prevent problems on your magnolia tree is to ensure that your tree remains healthy and strong so the tree will be in a better position to fight any problems if they occur.

You can do the following three preventive things to keep your magnolia tree healthy and looking good.

Proper Tree Pruning

1. The lack of proper air circulation through their leaves of magnolia tree causes many diseases on the tree.
2. Overcrowded or entangled branches will restrict sunlight and the air flow through its foliage. Regular pruning of your magnolia tree will ensure that your tree’s vitality and health is maintained.
3. Sometimes your magnolia tree may grow branches at strange angles, which will not damage the tree, but but make the tree look unattractive. You can prune such straggler branches once a year.
4. Prune the tree for shape as desired.

Correct Watering Magnolia Tree

Excessive moisture is also responsible for many problems and diseases on the magnolia trees. Watering on the foliage of your magnolia tree much water on the foliage will invite fungal diseases due to wet environment. Controlled watering by soaker hoses will ensure the correct amount of water without wetting the foliage and thus the tree diseases will not be there.

Droopy Leaves

1. Your magnolia tree may start to droop leaves. This happens if the tree is sitting in water for extended period of time.
2. Young or newly transplanted magnolia tree can also cause leaves to droop if the soil gets dried for long time. Check the soil,  If it is saturated, water the tree less if it mis saturated and water it if you see cracks in soil.

Deep Root Fertilization

Deep root fertilization is a method to inject liquid fertilizer directly in the root zone (How to fertilize magnolia trees). Deep feed your magnolia tree once a year like this to maintain a strong and robust root structure, making the tree disease resistant.

Video on growing magnolias