Research matters... control of Phalaenopsis flowers

The flowers of Phalaenopsis are attractive and long-lasting, and this orchid has become deservedly popular as a flowering pot-plant.

Plants can be kept vegetative by growing them at a temperature above 26 degsC because Phalaenopsis forms flowers only when grown for some weeks at a temperature lower than this. Once the vegetative plants are big enough, the air temperature can be dropped to a temperature that will encourage flower formation.

Recent research has demonstrated that flowering is controlled by the day temperature rather than the night temperature. Therefore the experiments reported here tested whether the day temperature had to be maintained above 26 degsC throughout the day period.

Plants of three clones of Phalaenopsis and one of Doritaenopsis were grown at constant temperatures of 20 degsC or 29 degsC. Other plants were grown at a basic temperature of 20 degsC, which was raised to 29 degsC for four, eight or 12 hours around the middle of each 16-hour day.

Flower formation was suppressed in Phalaenopsis 'Mosella' and 'Explosion', and was delayed in Phalaenopsis 'Golden Treasure' and Doritaenopsis 'Newberry Parfait' when the temperature was raised for 12 hours each day. This treatment would save energy, but it should probably be used only with the more responsive clones.

High-temperature Inhibition of Flowering of Phalaenopsis and Doritaenopsis Orchids by Newton and Runkle (2009). HortScience 44 (5): 1271-1276. Members of ISHS can view HortScience from the website,

Have you registered with us yet?

Register now to enjoy more articles and free email bulletins

Sign up now
Already registered?
Sign in

Read These Next

Tractors: market roundup

Tractors: market roundup

Manufacturers are working to provide solutions to many challenges. Sally Drury looks at their newest models.



Brightening up gardens in autumn, these daisies are seen as a gem in the gardener's arsenal, writes Miranda Kimberley.

Are tree suppliers seeing the benefit of the health message of trees?

Are tree suppliers seeing the benefit of the health message of trees?

The message that health, the environment and business all benefit from trees is finally getting through, but are nurseries seeing an upturn? Sally Drury reports.

Opinion... Why no-deal Brexit should worry you

Opinion... Why no-deal Brexit should worry you

Whether you voted leave or remain all those years ago, a "no-deal" Brexit should worry you.

I will not be importing oaks this season. Will you?

I will not be importing oaks this season. Will you?

I find myself in a difficult situation. A few weeks ago I was fortunate to be present to hear details of imminent changes to regulations concerning Oak Processionary Moth (OPM) and oak trees. I heard details, asked questions and probed the implications of these changes. That may not sound like a difficult position to be in, yet I am uneasy.

Opinion... Better targets to tackle pollution

Opinion... Better targets to tackle pollution

Lobby groups jumping onto fashionable campaigns, often to promote their own interests, can do much more harm than good. Take, for example, the move against black polythene plant pots and containers.

Follow us on:
  • Facebook
  • LinkedIn
  • Twitter
  • Google +
Horticulture Jobs
More Horticulture Jobs

Horticulture Week Top 60 Ornamentals nurseries

See our exclusive RANKING of ornamentals nurseries by annual turnover plus the FULL REPORT AND ANALYSIS

Tim Edwards

Boningales Nursery chairman Tim Edwards on the business of ornamentals production

Read Tim Edwards

Pest & Disease Tracker bulletin 

The latest pest and disease alerts, how to treat them, plus EAMU updates, sent direct to your inbox.

Sign up here

Are you a landscape supplier?

Horticulture Week Landscape Project Leads

If so, you should be receiving our new service for Horticulture Week subscribers delivering landscape project leads from live, approved, planning applications across the UK.

Peter Seabrook

Inspiration and insight from travels around the horticultural world

Read more Peter Seabrook articles