Which pests and diseases hit lemongrass and how do I manage them?

Lemongrass is one of the lower-pest aromatic crops because its strong citral smell deters many insects and grazing animals, which is part of why it suits unprotected marginal land. Still, it can get fungal leaf problems like leaf blight and rust, especially in very humid, crowded or waterlogged conditions, seen as spots or drying patches on leaves, and occasionally root or clump rot in poorly drained wet soil. Management is mostly cultural: keep good spacing and airflow, ensure drainage so the clumps are not standing in water, remove and destroy badly affected leaves, and harvest on time so old diseased growth is not left standing. Healthy, well-cut clumps with good airflow rarely have serious problems. Because the crop is distilled for oil, heavy chemical use is both usually unnecessary and undesirable, so lean on cultural control; if any disease becomes severe, consult your KVK for crop-specific advice and use only labelled products following PHI. Generally lemongrass needs far less spraying than vegetable or culinary-leaf crops, which is a real advantage. Keep the planting clean, drained and regularly harvested, and pest and disease losses stay minor.