Verdia · Library
Root and stem rot observations
Record drainage, standing water and potting mix before changing care, and see how Verdia routes Pythium, Fusarium and most Phytophthora names to root rot.
How root and stem rot names are matched
This group has 18 genera and no fallback keywords. It includes Phytophthora, Pythium and Globisporangium, Fusarium and Verticillium, Rhizoctonia and Armillaria, Ralstonia and Agrobacterium, and Meloidogyne. Three Phytophthora species are excluded: infestans, ramorum and capsici are caught first by the species map and go to mould and blight.
The app has three steps for this group, about drying the soil, checking roots and taking a cutting. None is repeated here, because each depends on knowing the cause.
The genus rule reads only the first word, so Fusarium oxysporum and Fusarium solani both land here, and so does any Verticillium name. A family-level result such as Pythiaceae matches nothing, because the group has no keywords.
Before changing anything
- Note whether the pot drains and whether water stands in the saucer.
- Record the condition of the potting medium: wet, dry, compacted or sour-smelling.
- Photograph the stem base and any wilting or yellowing leaves.
- Write down recent watering, so a change can be compared later.
Reading a Pythium result
A top result of Pythium aphanidermatum at 33 percent matches the genus pythium and opens the root rot steps in the app; this page lists none. Phytophthora cinnamomi would land here too. Phytophthora ramorum would not: the species map sends it to mould and blight before the genus rule is reached.
- Name returned
- Pythium aphanidermatum
- Top score
- 33%
- Rule that matched
- genus pythium
- Root rot steps shown here
- 0 of 3
Common errors
- Inferring from wilting alone that a plant needs more water, or complete drying.
- Confusing waterlogging with Phytophthora root rot, which can look similar.
- Repotting before recording drainage and the state of the mix.
- Assuming every Phytophthora name belongs to this group.
Scope
Wilting and yellowing show difficulty taking up water, not its cause. The RHS Phytophthora root rot page listed below describes one cause in detail; a specific assessment may be needed before acting, and the ASPCA list covers pet safety.