Fig rust

What you see

Small yellow-brown flecks on the upper leaf surface with rusty orange powdery pustules directly beneath. Leaves yellow and drop early, sometimes leaving the tree bare by late summer with fruit still ripening.

Conditions

Warm, humid weather and long dew periods in late summer, particularly after rain in August and September.

Treatment

Rake up and bin all fallen leaves - that is where it overwinters. Copper in late winter reduces carry-over. Mid-season spraying achieves little.

Prevention

Prune to open the canopy so leaves dry quickly. Avoid overhead watering. Clear leaf litter thoroughly every autumn.

Months: July, August, September, October

Plants

Fig

Remedies

Bordeaux mixture (copper)

The thing people get wrong

Losing fig leaves in September looks alarming and is almost always harmless - the crop ripens anyway and the tree refoliates perfectly next spring. It only matters if it strikes in July two years running, which starts to weaken the tree. The single effective action is autumn leaf clearance, done properly, because the fungus spends winter in that litter and nowhere else.