1. Plant Disease
  2. Host and Disease Descriptions

Privet (Ligustrum spp.)-Leaf Spot

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Latest revision: 
March 2024

Cause Cercospora spp. have been found by the OSU Plant Clinic in Oregon, and Ramularia sp. have been reported in Washington. Prevalent in rainy seasons and in overcrowded plantings. Spores are airborne or transported in splashing water. These fungi generally overwinter in leaf debris in and around plants.

Symptoms Irregular to circular necrotic leaf spots. Cercospora-infected leaves develop chlorotic spots or areas that expand to various sizes. Spots turn brown in the center with reddish-brown to purple borders. Some spots also may have a chlorotic (yellow) halo around them. Spots may coalesce and cause leaves to fall.

Cultural control

  • Space plants for good air circulation and quick drying.
  • Rake and destroy fallen leaves.

Chemical control Apply at 2-week intervals in wet weather.

  • Armada 50 WDG at 3 to 9 oz/100 gal water. Do not use a silicone-based surfactant. Not for nursery or greenhouse use. Group 3 + 11 fungicide. 12-hr reentry.
  • Bonide Fung-onil Multi-purpose Fungicide at 2.25 teaspoons/gal water. Group M5 fungicide. H
  • Daconil Weather Stik at 1.38 pints/100 gal water. Group M5 fungicide. 12-hr reentry.
  • Eagle 20 EW at 6 to 12 fl oz/100 gal water. Group 3 fungicide. 24-hr reentry.
  • Mancozeb-based products. Group M3 fungicides. 24-hr reentry.
    • Fore 80 WP at 1.5 lb/100 gal water plus a spreader-sticker.
    • Protect DF at 1 to 2 lb/100 gal water plus 2 to 4 oz spreader-sticker.
  • Myclobutanil 20 EW T&O at 6 to 12 fl oz/100 gal water plus spreading agent. May observe a PGR effect. Group 3 fungicide. 24-hr reentry.
  • Orkestra at 8 to 10 fl oz/100 gal water. Effective in Florida. Group 7 + 11 fungicide. 12-hr reentry.
  • Ortho MAX Garden Disease Control at 2 teaspoons/gal water. H
  • Pageant at 8 to 12 oz/100 gal water. Effective in Florida. Do not use with organosilicone-based adjuvants. Group 7 + 11 fungicide. 12-hr reentry.
  • Spectracide Immunox Multi-Purpose Fungicide Spray Concentrate for Gardens at 1 fl oz/gal water. Group 3 fungicide. H
  • Spectro 90 WDG at 1 to 2 lb/100 gal water. Group 1 + M5 fungicide. 12-hr reentry.

Reference Sobers, E.K. 1964. Cercospora diseases of Ligustrum. Proceedings of the Florida State Horticultural Society 77:486-489.