Viola × wittrockiana Gams ex Nauenb. & Buttler · Biennial
pansy leaf spot: Remove affected leaves promptly, thin the planting to improve airflow, avoid overhead watering, and lift badly affected plants rather than letting the disease carry over to neighbours.
downy mildew: Remove affected leaves, thin the planting to improve airflow, avoid overhead watering, and lift badly affected plants.
rots: Sort the cultural cause first — correct watering, drainage and airflow. Replace any plant that has collapsed with crown rot rather than nursing it.
aphids: Squash by hand on small plantings; use insecticidal soap only where the infestation is heavy and the product's label permits.