Troubleshooting
Manzanilla olive problems — and how to fix them
Manzanilla olive (Olea europaea 'Manzanilla') is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Olive knot
Caused by the bacterium Pseudomonas savastanoi; produces rough, gall-like swellings on branches and twigs. Prune out infected wood during dry weather, disinfecting tools between cuts. Copper-based bactericides applied at leaf fall and bud break help prevent spread.
Peacock spot (Spilocea oleagina)
Fungal leaf disease producing circular sooty spots with yellow halos on older leaves, causing premature defoliation. Most severe in cool, wet winters. Apply copper fungicide at leaf fall and again in late winter; improve air circulation through canopy thinning.
Frost damage
Manzanilla is less cold-hardy than some cultivars; temperatures below -7°C (-20°F) or hard frosts below -5°C on young wood can split bark and kill branch tips. Protect with fleece below -5°C; plant against a south- or west-facing wall in marginal areas.
Prevent manzanilla olive problems before they start
Most manzanilla olive issues are care-mismatch, not bad luck. Dial in the basics:
Looking for manzanilla olive in general rather than its problems? Read the full manzanilla olive care guide — light, water, soil and feeding.
Manzanilla olive problems — FAQ
Why is my manzanilla olive olive knot?
Caused by the bacterium Pseudomonas savastanoi; produces rough, gall-like swellings on branches and twigs. Prune out infected wood during dry weather, disinfecting tools between cuts. Copper-based bactericides applied at leaf fall and bud break help prevent spread.
Why is my manzanilla olive peacock spot (spilocea oleagina)?
Fungal leaf disease producing circular sooty spots with yellow halos on older leaves, causing premature defoliation. Most severe in cool, wet winters. Apply copper fungicide at leaf fall and again in late winter; improve air circulation through canopy thinning.
Why is my manzanilla olive frost damage?
Manzanilla is less cold-hardy than some cultivars; temperatures below -7°C (-20°F) or hard frosts below -5°C on young wood can split bark and kill branch tips. Protect with fleece below -5°C; plant against a south- or west-facing wall in marginal areas.