The choisya, aka Mexican orange blossom, is an evergreen plant which has a great advantage going for its well-being – it has scented flowers and leaves when crushed. And its citrus scent, produced in the spring and the end of autumn, works to keep bugs and disease away. You need worry about only a few choisya pests and diseases, and they’re easily dealt with.

Pests

Slugs and snails

These gastropods are the main choisya pests and they prey on young plants especially. As they eat the leaves, you can tell when they’re around by the holes in the foliage and their slime trail. To get rid of them, you can pluck them off manually and take them out of your garden. You can also deter them by using pellets to repel them.

If that doesn’t work, consider barriers that prevent them from reaching the choisya. They don’t like moving over gravel so place that around the plant stems. Or consider traps that catch the snails and slugs if they do make it as far as your plant. If growing in pots you can also get copper tape you stick the edge of the pot which they won’t cross.

You can also get copper rings you place around the base of your plant.

Red spider mite

This is a common mite that feeds on the sap of leaves. They’re usually found in indoor plants and in greenhouses, but they also attack choisya planted in gardens in summer too. Sucking the foliage sap makes the leaves take on a mottled appearance. The leaves can eventually fall off the plant.

Check your leaves for this damage. You usually notice the webs they create but you may also see the mites themselves even though they’re less than 1mm long. The mites are usually pale green/yellowish with two dark spots on their backs. However, in autumn and winter, they turn an orange-red colour. As already mentioned, you may also see signs of their webbing on the stems and leaves of the plant and maybe their eggs on the underside of the leaves. Your choisya could die through a bad infestation of these bugs.

The best way to eradicate spider mites is to make your plant and its environment inhospitable to them. Red spider mites like hot, dry conditions, such as in a greenhouse though not so much outdoors. Give your choisya plenty of room to grow and for air to circulate through its branches. Ensure that plant is adequately watered and spray the leaves with water in the driest part of the summer.

You can also introduce another insect, such as lady birds/bugs, that eat the mites. The last alternative to use is a commercial pesticide, especially for this problem. But don’t use this when the bush is in flower as that may harm its pollinators such as bees and butterflies.

Diseases

If disease hits your choisya, it’s usually because of its poor growing conditions and usually related to drainage. If the Mexican orange blossom is planted in heavy soil or soil that’s too slow to drain, it becomes waterlogged. This encourages fungal diseases to move in.

Root rot

Root rot develops in damp and cool weather or if the shrub is in too much shade. This is a sun loving plant and needs a full day’s quota of sunlight. Root rot kills the underground roots. You may not even notice that this is going on until the whole plant starts suffering.

Another form of rot is crown rot. This refers to the place further up the bush where the root and the trunk system meet. Again, you may not see that anything is wrong until the leaves and branches stop receiving their needed flow of water and nutrients and they start dying. You can learn more about why your choisya might be dying in this guide here

The solution to root rot is to ensure that your shrub is planted in well-drained soil, has an adequate amount of sunlight, the correct amount of water and enough nutrients to keep it in a healthy state.

Grey mould

The same adverse conditions of dampness, cool weather and stagnant air can lead to grey mould. This is a fungus that grows on healthy leaves and stems. It can cause the stems to die on the choisya plant.

There’s nothing you can do if you find grey mould as, by then, the tissues of the plant are probably dead and rotting. It appears as streaks of grey spores on dead plant tissues. I usually recommend replacing the plant.

I also have a guide on why choisya can start wilting and turning yellow here

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