A few key disease vectors infect the hyacinth, causing damage to flowers, stems, leaves, roots and the bulb. Here are tips on how to identify, treat and prevent these diseases in your hyacinth plants.
Yellow rot turns hyacinth leaves yellow and waterlogged, then forms brown spots on leaves. The weak stems will turn brown and shrivel. Yellow slime is visible in a stem cross-section. This disease forms in soil that is too damp. You must dig out and destroy infected plants.
Black slime attacks the hyacinth plants through the bulb. Look for yellowing leaves that detach easily from the stems. Destroy the plants, and treat infested soil with a strong fungicide.
Root rot, caused by the Fusarium oxysporum fungus, produces dwarfism and poor-quality flower buds in hyacinth. You must destroy infected bulbs.
Look for gray moldy growth on hyacinth leaves. Flowers will rot on the stems. Botrytis cinerea is the fungus behind gray mold.
Spread by nematodes that attack the bulbs, you can recognize mosaic by blue-green discoloration on the leaves. Destroy the bulbs and treat the soil with a nematode pesticide.
Defend hyacinths against these diseases by watering sparingly and transplanting only into healthy, grub-free soil.