# Gardening fixtures

**Deviation from the planned protocol:** the plan called for two photos of the operator's own plants. These are two openly licensed photographs from Wikimedia Commons, chosen because the plant and the problem were identified by the photographer (one of them a plant pathologist), which gives a ground truth the tools can be scored against. Both are resized to 1400 px on the long side; the originals are at the URLs below. The context line in the brief was changed from "north-facing windowsill" to "north-facing terrace" because both photographs are visibly outdoors.

## plant-a.jpg — Clivia miniata with citrus mealybug

- Source: https://commons.wikimedia.org/wiki/File:Citrus_mealybug_Planococcus_citrus_on_Clivia_miniata_01.jpg
- Author: Sinikka Halme, 2018-06-24. Licence: CC BY-SA 4.0.
- Ground truth: plant **Clivia miniata** (bush lily / Kaffir lily, Amaryllidaceae); problem **citrus mealybug, Planococcus citri** - white cottony masses and crawlers on the strap leaves.
- Right plan, per the RHS and UC IPM guidance on mealybugs: isolate the plant; remove the visible bugs (cotton bud or brush with 70% isopropyl alcohol, or a strong jet of water); treat with insecticidal soap or horticultural oil, repeating weekly for several weeks because eggs and crawlers hide in the leaf bases; check the leaf axils and the pot rim; expect a slow fix, not a one-off. Watering every 3 days is too much for a Clivia (it likes to dry out between waterings and rots easily) - a good answer says so.

## plant-b.jpg — Begonia with powdery mildew

- Source: https://commons.wikimedia.org/wiki/File:Begonia_Powdery_mildew_(16112475571).jpg
- Author: Scot Nelson (plant pathologist, University of Hawaiʻi), 2014-12-26. Licence: CC0.
- Ground truth: plant **Begonia** (a bronze-leaved wax / semperflorens-type bedding begonia with red flowers); problem **powdery mildew, Oidium begoniae** - white powdery patches on the upper leaf surfaces, some leaves distorted or dying back.
- Right plan, per the RHS and UC IPM guidance on powdery mildew: remove and bin the worst leaves; improve air movement and spacing; water the soil, not the leaves, and do it in the morning; avoid drought stress and over-feeding with nitrogen; a fungicide (sulphur, potassium bicarbonate or a labelled product) slows it but does not cure affected leaves; expect the plant to recover with new growth. Every-3-day watering is not the cause; overhead watering and poor airflow would be.

## Scoring notes

- Identification: genus right (Clivia / Begonia) counts as identified; species is a bonus.
- Diagnosis: A = mealybugs (any of "mealybug", "cochonilha", "Planococcus", "scale insect (mealybug)"); B = powdery mildew (any of "powdery mildew", "Oidium", "oídio"). "Fungus" alone for B, or "pest" alone for A, counts as a plausible partial.
- Plan: specific to the diagnosis (alcohol/soap/oil and repeat for A; remove leaves, airflow, don't wet foliage, fungicide for B) versus generic care.
- Context: does the answer use "north-facing terrace" and "every 3 days" - for A a good answer flags the watering; for B it flags foliage wetting/airflow rather than frequency.