Recovery from hail damage for avocado trees

It's important to inspect damage of avocado trees as soon as possible after a hail event as the level of damage can be obscured by subsequent growth.

Hail can impact on the foliage, flowers, stems, branches and fruit in various ways:

Trees can be completely stripped of leaves and fruit.
Leaves can be bruised, torn, tattered, have holes in them or be completely knocked off the plant.
Stems and branches can be broken or bruised and scarred.
Flowers can be damaged but this is difficult to assess unless flowers have been knocked off the plant.
Fruit can be bruised or knocked to the ground.
Pests and diseases can enter fruit and bark through wounds caused by hail.
Fallen fruit can harbour pests and diseases.

Those with hail damage insurance should contact their insurer and arrange for damage assessment.

Management of hail-damaged trees

The following tips can help you manage trees damaged by hail:

Prune off severely damaged stems and branches as soon as possible to prevent infections.
Apply fertilisers and irrigation at optimum levels to help the trees overcome the stress caused by the hail damage.
Remove fruit that has fallen to the ground to reduce the risk of pests and disease.
Consider harvesting exposed fruit earlier to avoid sunburn damage. There is the potential for sunburn where foliage has been stripped, exposing fruit.
Inspect damaged plants more frequently for pests and diseases.

Wounds are a key infection site for disease, and particularly bacterial diseases:

It may be useful to apply a fungicide to protect wounded branches and fruit from disease (although damaged fruit are likely to be unmarketable). Be careful using fungicides if bee pollination is occurring. Read labels on chemicals and follow instructions carefully. Contact your local reseller for advice on a suitable fungicide.
Where practicable, cover wounds on trunks and branches with a water-based paint to avoid desiccation and disease infection.

For more information, contact:

Antony Allen, CEO, Avocados Australia

Simon Newett, Principle Extension Horticulturalist, Agri-Science Queensland

Page last updated: 22 Jun 2020