Hoya ‘Joy’

Origin of Hoya ‘Joy’

Michael Miyashiro raised ‘Joy’ in Hawaii from a cross reported as an unidentified Hoya from Laos × Hoya vitellina. ‘Metallica’ came from another seedling of the same cross.

Care for Hoya ‘Joy’

• Support and leaf space: Use loose ties while the runner is flexible; older growth should remain in place. A restrictive tie can damage the stem and stall the runner above it.
• Light around the foliage: Set the plant near a bright window without harsh direct sun. Keep the newest blade clear of neighbouring foliage that blocks the light.
• Watering: Wait until the upper layer is dry before the next thorough watering. Keep watering consistent while new shoots develop.
• Potting mix: Use bark and mineral particles around the roots, and keep moss loose at the stem base. Avoid packing moss tightly around the lower stem.
• Broad glossy leaves: Give each new blade enough room to open without touching the support or neighbouring foliage. Fine silver flecks are part of the leaf and remain fixed after it hardens.
• Temperature and airflow: Keep the hybrid away from cold window edges and enclosed humid corners where leaves remain damp. Choose one position away from cold glass and hot vents, and avoid moving the plant repeatedly between rooms.
• Feeding: Use modest feed while the runner is growing. Pause feeding while the root zone is cool or persistently wet.

Common issues with Hoya ‘Joy’

• A broad glossy leaf develops a permanent scrapeLikely cause: The blade rubbed against the support before the petiole had hardened.What to do: Move the vine onto a wider, rigid support and fasten the stem below the petiole. Give the new blade room to expand without touching the support. Keep a firm marked leaf; prune only tissue that splits, blackens or softens.
• The vine stretches and produces pale leavesLikely cause: Light is failing to reach the tip because of self-shading or placement.What to do: Shift the support into brighter indirect light and let the newest node face the source.
• Silver-marked leaf edges brown shortly after fertilisingLikely cause: The fertiliser dose was too strong while the vine was growing slowly in limited light.What to do: Pause fertiliser, flush the root zone with plain water and remove all runoff. Return to a lower fertiliser dose after healthy new growth appears.
• Sticky residue gathers around misshapen new leavesLikely cause: Sap-feeding insects are sheltering around the tender tip or beneath the broad blades.What to do: Move the plant away from nearby vines and inspect the nodes with a hand lens. Remove visible scale or mealybugs with a damp cotton pad, then treat the entire plant with a patch-tested insecticidal soap. Inspect the next unfolding leaf and repeat treatment only at the interval permitted on the product label while live pests remain.

Hoya ‘Joy’ and pet safety

Hoya ‘Joy’ is treated as non-toxic to cats and dogs. Chewing leaves or stems can still cause temporary drooling, vomiting or diarrhoea. Keep the plant out of reach of pets that chew foliage, and contact a veterinarian if symptoms are severe or persistent.

The hybrid name ‘Joy’

The name ‘Joy’ applies to this Michael Miyashiro hybrid. ‘Joy’ and ‘Metallica’ are separate sister seedlings from the same reported cross.