There are no pesticides available to home gardeners which will control foliar nematodes. Cultural methods can be used to reduce infestations and minimize damage.
Purchase nematode-free plant material
Avoid introducing foliar nematodes into your garden by thoroughly inspecting plant material for symptoms and buying from reputable suppliers.
Sanitation is critical for control
To manage and restrict spread remove and dispose of all infected plant material and control weeds which could be potential hosts. Thoroughly clean contaminated gardening equipment and muddy shoes. See disposal of diseased material for more details.
Avoid overhead irrigation
The mobility of nematodes on the surface of plants depends on the presence of a water film so avoid overhead irrigation such as sprinklers to reduce the risk of dispersing nematodes between plants.
Host plants vary in susceptibility but the knowledge of which varieties are resistant is lacking. Research conducted in the first half of the 20th century indicated that chrysanthemum varieties varied in susceptibility to foliar nematode. Some varieties that may be commercially hard to find (e.g. ‛Amy Shoesmith’, ‛Orange Beauty’ and ‛Orange Peach Blossom’) were shown to be resistant but not immune. Foliar nematodes can invade these cultivars but females produce few eggs and juveniles so usually fail to mature. In time the nematode population will fall to insignificant numbers. There is a need for more research in this area as there have been significant advances in breeding.