Citrus tree care: Common issues and how to control
Tackle common issues with citrus trees with the helpful advice of Wynne MacLellan, Fruitfed Supplies Technical Horticultural Representative, based out of Gisborne.
Firstly, let’s look at prevention. Spray your trees monthly with a broad-spectrum copper spray such as Yates’ Copper Oxychloride Fungicide. This will help prevent fungal diseases such as downy mildew, rust, fire blight and citrus scab. Another option is Yates’ Lime Sulfur which creates a film over fruit trees protecting against fungus and a range of insect pests and diseases.
A healthy citrus tree is a well-fed one according to Wynne as it is better equipped to fight disease and pest invasions. Feed in spring and autumn using a fertiliser such as Tui’s Citrus Mix or Tui’s Citrus Food. To help protect against a magnesium deficiency, that presents as yellowing leaves, try Tui’s Epsom Salts Magnesium Sulphate.
In springtime, apply a seaweed tonic such as Tui’s Organic Seaweed Plant Tonic to help build resilience to stressors such as temperature extremes, insect pests and disease.
Now to treatment. Wynne recommends Yates’ Conqueror All Seasons Oil to control scale, an insect pest commonly found in citrus trees. Another common insect pest, whitefly, usually infects a tree during the period of new growth so control using a product like Kiwicare’s Organic Super Spraying Oil which is suitable for organic growers and registered for use in and around fruit. Another option is Yates’ Nature’s Way Organic Citrus, Vegie & Ornamental Spray which will control both scale and whitefly and includes seaweed to aid the trees recovery from infestations.
If you need help identifying what critter is invading your citrus tree, take a photo of the insect and bring it to your local PGG Wrightson store for help. The team will be able to provide you with a recommendation on a suitable product to use.
- Regularly inspect your fruit trees for insect pests and disease. If you catch an infestation quickly, Wynne says it is a lot easier to manage.
- Treat your citrus trees with a preventative treatment such as one of the options mentioned above.
- Feed and water your trees. If you want a healthy yield with good sized fruit, water your trees through spring and summer right through to March when the fruit has matured.
- Thin branches inside the tree to encourage light to travel to the centre of the tree. This will reduce insect pests who love dark and moisture from making the tree a home.