Do not establish Verticillium-susceptible perennials where the season log records that a Verticillium host (strawberry, raspberry or other bramble, or stone fruit) previously grew — a reservoir the coarse prior-nightshades family signal structurally misses.
Promising · costly if ignored → warn
How it works
The same reservoir as the family-level rule — Verticillium dahliae persisting in soil as microsclerotia — but recognised precisely instead of coarsely. The family-level rule fires on a prior nightshades family, which is all a manual history checkbox can express; this rule fires on the logged planting's own species carrying the verticillium_host marker, so a prior rose family host (strawberry, raspberry, stone fruit) counts while a non-host rose family like apple correctly does not — precision the family signal cannot give.
What to do about it
Site the perennial where the log shows no previous Verticillium host, or choose one that is not susceptible. Extension advises growing a non-host — corn or a small grain — for at least two years first, without claiming that clears the soil. Once the perennial is planted there is no in-ground cure.
How much it matters: Same guidance as another rule here: avoid establishing brambles or strawberries after a Verticillium host, and grow a non-host (corn or a small grain) for at least 2 years first. Microsclerotia can persist for up to ~10 years, and the number of years required to eliminate the pathogen is described by extension as unknown.
The evidence
Evidence: confirmed against 3 sources in the research-based literature.
the 3 sources
Penn State Extension, 'Bramble Disease - Verticillium Wilt' (Kathy Demchak), extension.psu.edu/bramble-disease-verticillium-wilt (read 2026-07-12): 'To minimize disease, choose a planting site with no known history of this problem. Avoid land recently planted with tomatoes, potatoes, eggplants, peppers, strawberries, raspberries, or stone fruits'; 'There are no effective fungicides for management once the plants are in the ground.'
UMass Extension, New England Small Fruit Management Guide, 'Brambles - Diseases', ag.umass.edu/fruit/ne-small-fruit-management-guide/brambles/diseases (read 2026-07-12): 'Verticillium attacks a wide range of plants, including potatoes, tomatoes, peppers, eggplant and strawberries.'; 'Non-host crops such as corn or wheat can help eliminate the fungus if grown for at least 2 years before planting raspberries.'
Host range / persistence corroborated by NC State Extension, 'Verticillium Wilt of Tomato and Eggplant' (read 2026-07-11): microsclerotia survive 'up to 10 years' and the pathogen 'affects more than 300 host families.'