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Control Blackspot in the garden


August 1, 2022


Searles Gardening Team

What are Black Spot symptoms?

Black spot is a real problem on roses, but can also affect fruit trees such as citrus, paw paw and apples. Black spot is a fungal disease which appears as black spots on leaves initially, then turns the leaf yellow and drops off. Black spot spores can be spread by wind and contact with an affected plant. Rose growers take great pride in growing their prized beauties and Black spot is an unsightly welcome that needs to be treated promptly.

Black spot is generally seen in cool weather or periods of wet weather and loves humid warm climates. Plants lacking in minerals and unbalanced soil structure are more susceptible to this disease also. It is very important to keep roses and fruit trees healthy.

How to control Black Spot

  • Thin the bush's canopy to promote air movement around the branches by removing dead and old branches.
  • Water plants at the roots and not the leaves. Watering leaves especially at night promotes Black spot. A good practice is to water early mornings.
  • Like humans, healthy plants can resist disease better than unhealthy plants. Feeding roses and fruit trees with SeaMax Organic Fertiliser Liquid will aid the plant in reducing pests and diseases, harsh weather changes and transplant shock.
  • Keep pruning and garden tools clean. Fungal diseases spread easily by contact.
  • If black spot is present pick off and bin affected branches.

For severe cases, spray with the following sprays for effective treatment.
Roses & pome fruit - use either Searles Mancozeb Plus or Mancozeb.
Roses - use either Trifend or Rose Pro.
Citrus - use Copper Oxychloride.