Houseplants

Dendrobium

DendrobiumOrchidaceae
Also: Dendrobium orchid, Noble dendrobium, Cane orchid, Cooktown orchid
Noble dendrobiumCane orchid

Noble dendrobium

Very different from the moth orchid: this one needs a cool, bright, dry autumn to flower, not a warm living room all year.

Bright indirect light Water: average H1cabove 5 °C 30–60 cm tall · 20–40 cm wide In a pot: yes
Flowering · UK
Flowering · Northern Italy
Flowering · Central Italy
Flowering · Southern Italy and islands

Care

Light

Bright light with some gentle direct sun; a cool, bright spot in autumn is what sets flower buds.

Water

Medium in summer, then almost dry from autumn until buds show — a cool, dry rest is essential, or the plant makes baby plants instead of flowers.

Soil

Coarse orchid bark in a small pot that drains freely.

Pruning

Don't cut old leafless canes: they flower again and store water. Remove only canes that are shrivelled and brown.

Feeding

Orchid feed at every second or third watering while new canes are growing, then stop completely from autumn so the canes ripen — late feeding is the main reason for no flowers.

Propagation

Pot up the small plantlets (keikis) that form on the canes once they have roots a few centimetres long; large plants can be divided when repotting.

Month by month

Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.

  1. MayRepot after flowering if the bark has broken down, into a pot only just big enough. how ›
  2. JuneCan summer outdoors in a sheltered, lightly shaded spot. how ›
  3. SeptemberBring in before nights drop below 10°C and keep somewhere cool and bright. how ›
  4. OctoberStop feeding and keep nearly dry until flower buds appear. how ›

Months based on climate: UK. Your choice stays on this device.

  1. MayRepot after flowering if the bark has broken down, into a pot only just big enough. how ›
  2. MayCan summer outdoors in a sheltered, lightly shaded spot. how ›
  3. SeptemberBring in before nights drop below 10°C and keep somewhere cool and bright. how ›
  4. OctoberStop feeding and keep nearly dry until flower buds appear. how ›

Months based on climate: Northern Italy. Your choice stays on this device.

  1. AprilRepot after flowering if the bark has broken down, into a pot only just big enough. how ›
  2. MayCan summer outdoors in a sheltered, lightly shaded spot. how ›
  3. OctoberBring in before nights drop below 10°C and keep somewhere cool and bright. how ›
  4. OctoberStop feeding and keep nearly dry until flower buds appear. how ›

Months based on climate: Central Italy. Your choice stays on this device.

  1. AprilRepot after flowering if the bark has broken down, into a pot only just big enough. how ›
  2. AprilCan summer outdoors in a sheltered, lightly shaded spot. how ›
  3. OctoberBring in before nights drop below 10°C and keep somewhere cool and bright. how ›
  4. NovemberStop feeding and keep nearly dry until flower buds appear. how ›

Months based on climate: Southern Italy and islands. Your choice stays on this device.

Common problems

Keikis instead of flowers

How to spot it. Small plantlets grow from the canes where flowers should be.

What to do. Winter too warm or too wet; give a cool, dry rest next autumn.

Mealybug and scalefull sheet ›

How to spot it. White fluff or brown bumps at leaf joints.

What to do. Wipe off with a cotton bud dipped in alcohol; repeat weekly.

Root rot

How to spot it. Soft brown roots, canes shrivelling despite watering.

What to do. Repot into fresh bark, cutting away dead roots.

Cooktown orchid

Cooktown orchid

The warm-growing dendrobium: treat it like a moth orchid, but give it more light.

Bright indirect light Water: average H1aheated glasshouse 30–70 cm tall · 20–30 cm wide In a pot: yes
Flowering · UK
Flowering · Northern Italy
Flowering · Central Italy
Flowering · Southern Italy and islands

Care

Light

Bright light, including some morning or winter sun; more light than a moth orchid.

Water

Medium — water when the bark is nearly dry; slightly drier in winter but without a hard rest.

Soil

Coarse orchid bark in a small, free-draining pot.

Pruning

Cut the flower spray off once it fades. Keep old canes; they can flower again.

Feeding

Orchid feed at every second watering while growing, less in winter.

Propagation

Division when repotting, or potting up keikis once rooted.

Month by month

Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.

  1. AprilRepot every two years into fresh bark if needed. how ›
  2. JuneFeed at every second watering during growth. how ›
  3. NovemberKeep warm (above 15°C) and in bright light while flowering.

Months based on climate: UK. Your choice stays on this device.

  1. AprilRepot every two years into fresh bark if needed. how ›
  2. JuneFeed at every second watering during growth. how ›
  3. NovemberKeep warm (above 15°C) and in bright light while flowering.

Months based on climate: Northern Italy. Your choice stays on this device.

  1. MarchRepot every two years into fresh bark if needed. how ›
  2. JuneFeed at every second watering during growth. how ›
  3. NovemberKeep warm (above 15°C) and in bright light while flowering.

Months based on climate: Central Italy. Your choice stays on this device.

  1. MarchRepot every two years into fresh bark if needed. how ›
  2. JuneFeed at every second watering during growth. how ›
  3. DecemberKeep warm (above 15°C) and in bright light while flowering.

Months based on climate: Southern Italy and islands. Your choice stays on this device.

Common problems

How to spot it. Buds yellow and fall before opening.

What to do. Cold draughts or moving the plant; keep it warm and in one place.

How to spot it. White fluffy patches at leaf joints.

What to do. Remove with alcohol on a cotton bud.

Wrinkled canes

How to spot it. Canes shrivel.

What to do. Either underwatering or rotted roots — check the roots before watering more.

Questions

Dendrobium: is it hardy?

Noble dendrobium: H1c: Tender, needs above 5°C. It survives above 5 °C. Cooktown orchid: H1a: True houseplant, needs above 15°C. It survives heated glasshouse.

Can it grow in a pot?

Noble dendrobium: Yes — grown in small pots of orchid bark. Cooktown orchid: Yes — a warm-growing houseplant orchid.

Dendrobium: when do you prune it?

Noble dendrobium: Don't cut old leafless canes: they flower again and store water. Cooktown orchid: Cut the flower spray off once it fades.

Dendrobium: when does it flower?

Noble dendrobium: In the climate of UK it flowers in January–April. Cooktown orchid: In the climate of UK it flowers in September–December.

When do you feed it?

Noble dendrobium: Orchid feed at every second or third watering while new canes are growing, then stop completely from autumn so the canes ripen — late feeding is the main reason for no flowers. Feeding months, UK: April–August. Cooktown orchid: Orchid feed at every second watering while growing, less in winter. Feeding months, UK: March–September.