Disease problems can be reduced by not growing
sunflowers in the same location for more than 3 or 4 years in a row.
Many varieties have limited resistance to diseases such as
wilt, downy mildew and rust. These problems may build up in crop
residues or in the soil and increase in severity when the same crop is
planted in the same location for many years.
The major diseases of sunflowers are downy mildew,
rust, Sclerotinia stalk and head rot,
Verticillium wilt, Phoma black
stem and Alternaria leaf and stem spot.
Insects that attack sunflowers include sunflower head
moth, banded sunflower moth, and the sunflower weevil.
A number of birds will eat sunflower plantings but blackbirds seem to
be the most damaging.