Pleurothallis urseolata – 365 days of orchids – day 1166


We have some very flowery orchids in the greenhouse this weekend but this may win on flower count alone.

Many pleurothallis species are small plants or even tiny miniatures but some like this species are large dramatic plants with thousands of small flowers on a mature plant. This plant stands 60cm high and is still a relatively young plant.

The flowers have been in bud (like tiny bird’s beaks) for a while and it does take a close inspection to see the fine thread like petals that show flowers have opened. The flowers are not large but the long pendulous flower spikes are very attractive especially since individual leaves can produce up to ten flower spikes.

Pleurothallis urceolata is native to Ecuador where it grows in cloud forests from 1500-2900m altitude and in common with many of the larger leaved pleurothallis it enjoys being kept wet and shaded especially in the summer when overheating can lead to dark blotches on the leaves. This species produces abundant roots which makes culture easier especially in warm weather.


Cattleya trianae – 365 days of orchids – day 1165

It was snowing hard as I arrived at school yesterday morning (it didn’t settle) but inside the greenhouse the mood was much more tropical with the National Flower of Colombia – Cattleya trianae painting a flamboyant picture against the snow speckled glass.

IThis is the standard form of the species with large pink flowers with a deep pink and yellow lip, but we have three clones flowering at the moment.

Cattleya trianae is endemic to that Colombia – so a great choice for National Flower. In our greenhouses it always flowers in February and March where its very large flowers always create a stir.

The other clones in flower this week are our Cattleya trianae ‘albas’ which are yellow and white apart from a slight pink edge to the lip (see below) so we call them albescens rather than alba, and C. trianae coerulea that has blueish lilac colour.

We grow all our Cattleya trianaes in baskets filled with a course bark and no moss. The plants produce masses of roots and we keep them just damp in the winter but much wetter when in summer growth. We hang the baskets up in Warm Americas where they get lots of light (the auto shading is activated at 500 Whatts/ square metre)


Trichoglottis pusilla – 365 days of orchids – day 1164

This species won miniature orchid of the year, 2019, in our public vote, and I understand why.

The plants are tiny (5cm across) and the flowers are relatively large and wonderfully striped.

Trichoglottis pusilla is native to Java where it grows in rain forest from 1000 to 2000m altitude. We grow this species mounted in Warm Asia where it lives high up but shaded on a mesh frame that allows good air movement but easy spraying with rain water and feed every day.

As you can see we have two clones that are different in the flower shape and habit but in recent years the two clones’ flowers open within a day of each other. The flowers are long lasting and will be a treat for any visitors over the next four weeks.


Coelogyne lawreneana – 365 days of orchids – day 1163

I am surprised to find that we have never featured this large flowered coelogyne on 365 days – it is long overdue.

Coelogyne lawrenceana is a warm growing species from the Himalayas through to Vietnam. We have seen related species in Laos as terrestrials and epiphytes usually growing in shade with luch green leaves and large pseudobulbs. The 10cm wide flowers are produces successively on spikes from the top of the bulbs giving months of flowering. The lip of the species is particularly beautiful with unusual raised crests and nobbles.

We grow the species in our Warm Asia section and find that the secret to good flowering is feeding and watering plants very well during the summer. If plants are kept too dry. they produce smaller bulbs that do not flower.


Dendrobium infundibulum – 365 days of orchids – day 1163

This large flowered, dramatic Dendrobium (the pseudobulbs are now over 1m in length) is native to the Eastern Himalayas from Assam through China, Thailand, Laos and Vietnam. We find it does best grown warm (we give it a minimum of 16C) where it seems to flower well without a marked rest period. The long pseudobulbs are particularly attractive with their covering of dark hairs. Flowers are produced in groups from the older pseudobulbs and so as the plant matures the flower count keeps increasing.

On our expeditions to Laos we have found its habitat in evergreen forest with hot wet summers and dryer cooler winters although dew is significant in the dry season leaving the forest damp every morning. It grows amongst the white Rhododendron lyi which it mimics, and is pollinated by a large bumble bee (Bombus eximius) that is hoping it is a rhododendron flower full of nectar. The orchid flowers before the rhododendron as bees that have seen both are not so easily fooled. The research, which I first read in the nineteen eighties, is really thorough and left a strong impression on a younger me.

(reference – Kjellsson, Gösta & Rasmussen, Finn & Dupuy, David. (1985). Pollination of Dendrobium infundibulum, Cymbidium insigne (Orchidaceae) and Rhododendron lyi (Ericaceae) by Bombus eximius (Apidae) in Thailand: a possible case of floral mimicry. Journal of Tropical Ecology. 1. 289 – 302.)

The species flowers several times each year and the individual flowers, although looking papery, last for two months.