How to Use Nematode Repellent Plants. From Gardening Know How.
- Two of the best plants for nematode control are the painted daisy and French marigold. Both of these are not just nematode repellent plants, but they actually kill nematodes more efficiently.
- Painted daisy (Chrysanthemum coccineum) is useful for warding off nematode problems because it produces a botanical toxin that kills root nematodes. A source is here.
- French marigold (Tagetes patula and Tagetes erecta*) produces a natural chemical that kills several types of nematodes, including the root-knot nematodes that attack carrots and many other vegetable plants.
- Scientists have found that Tangerine, a dwarf French marigold variety, is especially effective at combating nematodes in garden soil. Tangerine Gem, Tagetes signata will NOT control root-know nematodes.*
- The following varieties of French marigold are also effective: Bolero, Bonita Mixed, Goldie Gypsy, Sunshine Petite, Petite Harmony, Petite Gold, Scarlet Sophie
*. NCDA&CS paper, Root-knot Nematodes: Biocontrol with Marigolds dated January 2006. here