What's eating my vanda 'robert's delight'?

Vanda 'Robert's Delight' is a tropical monopodial orchid typically grown in a warm, humid greenhouse or bright indoor space with bare roots. Spider mites are the top threat in low-humidity indoor conditions. Mealybugs and scale colonise the leaf axils and exposed aerial roots. Thrips can damage the large, colourful blooms. Good airflow is essential.

Silvery stippling and bronzing on broad strap leaves; fine webbing on undersides in dry air. Mist or dunk aerial roots and foliage daily; spray with insecticidal soap or neem oil every 5–7 days. Maintaining high humidity is the best prevention.

White cottony fluff in leaf axils and along the root-leaf junctions; sticky honeydew and sooty mold. Dab with isopropyl alcohol on a cotton bud; spray the entire plant including roots with diluted neem oil; repeat weekly.

Oval tan or brown shells on leaves and aerial roots; weakened plant with yellowing foliage over time. Scrape off physically, then apply horticultural oil to all surfaces including aerial roots; repeat in two weeks.

Silvery scarring and tiny black frass on large flat flowers; petals appear dull or streaked. Hang blue sticky traps; apply spinosad spray to foliage; remove and destroy affected blooms promptly.