Narcissus eelworm
Symptoms
Although the pest cannot be seen, the plant will suffer from
stunted growth and may show yellowish foliage. Eventually, the
bulbs die off leaving bare patches in planting swathes. This
problem will get worse in successive years. If you suspect
Narcissus eelworm, dig up and cut open a bulb. You will see rings
of brown dead tissue.
Spot them
These pests are not visible to naked eye.