CultivaOS
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Leaf spot

Fungal diseaseLow impact

Dark or water-soaked spots on basil leaves caused by fungal or bacterial pathogens. Typically affects leaf quality rather than plant survival, but can make leaves unsightly and unfit for harvest.

Currently in peak season - extra vigilance worthwhile.

Key facts

Type
Fungal disease
Affects
Basil
Active season
Jun - Sep
Peak season
Jul - Aug
Vulnerable stages
Growing · Harvesting
Spread rate
slow
If confirmed
Act soon

Signs & symptoms

  • -dark brown or black spots on leaves, sometimes with a yellow halo
  • -water-soaked-looking areas that later turn brown
  • -damaged leaf edges or irregular blotchy discolouration
  • -leaf drop in more severe cases

Management

Do now

  • -Remove and bin affected leaves - do not compost
  • -Avoid overhead watering and wetting foliage

Prevention

  • -Space plants at recommended distances to allow airflow
  • -Water at the base rather than over the foliage
  • -Remove dead or dying plant material promptly throughout the season

Further reading

  • -Leaf spot on basil is usually an opportunistic infection following stress - maintaining good growing conditions is the primary prevention