365 days of orchids – day 577 – Stelis itatiayae

I mentioned yesterday that our first contact with stelis species was in Brazil and this is one of the species found in the Mata Atlantica around our base in Macae de Cima.

Unlike yesterdays Stelis reginae, which is large growing with 15cm leaves and 5mm flowers, Stelis itatiayae is a real miniature with 4cm leaves but impressive erect flower spikes and relatively large hairy and attractive flowers.

The species is found in wet forest from 900-1400m  in the low trunk area so enjoys good humidity and we find it loves a 3cm mossy pot.


365 days of orchids – day 576 – Stelis reginae

We have featured lots of Stelis species on 365 days and it is one of our favourite genera. Many species produce a magnificent display of lots of  flowers. We first became aware of the genus in Brazil where we saw lots in flower and we saw more species in our visits to Costa Rica.

Stelis reginae is one of the larger flowered Stelis and is endemic to Ecuador where it is found in wet cloud forest at 1800m. We therefore grow the species cool and wet all year. It  has flowers with a very attractive pink edging against the cream ground colour and our large specimen flowers for many months over the summer and autumn.

We find that growing specimen plants of Stelis or Pleurothallis is easier in baskets than pots as the compost says in good condition for longer and the plants can form a natural ball rather than growing out of their pot.

Look out for more stelis species over the next few days as we have several looking at their best this week.


365 days of orchids – day 575 – Pleurothallis gracillima

We will start the month of August with a great example of a ‘miniature’ orchid that can grow into a specimen. Plants flower well as tiny plants in 3cm pots or mounted but if left for long enough (the plant shown has been growing in its current basket for ten years) forms a ball that is covered in its delicate sprays of pink and yellow flowers.

This species of Pleurothallis is native to the cloud forests of Colombia and Ecuador. It is another from the Specklinia section and is a small growing species that produces masses of flower in the summer but can produce the odd spike at any time in addition.

We find it grows well mounted or in pots and baskets. We grow the species in Cool Americas with lots of water especially in the summer when it is in most active growth.


Rain beautiful rain

The sky is blue again over the school greenhouse but we have enjoyed a wet couple of days and our rain water tank has gone from very nearly empty to 1/3 full again. Our tank holds 16 000 litres and this month we have been down to our lowest level ever (about 1000 litres). We have been asked what we do if we run out of rain water but so far this has never happened. If we did run out of rain water we would have to use tap water but this would give us limescale deposits on all our leaves as well as reducing the amount we can feed safely in the summer (we can add more feed to rain water than tap water because the total dissolved salts level is so low in rainwater)

The hot spell has been a challenge for some of our cool loving plants as the greenhouse has regularly reached temperatures above 30C. Our policy is not to worry too much but make sure that plants are well watered so that they can cool with transpiration. A few plants have suffered from heat stress like this Masdevallia species which has dropped leaves

Some plants however have loved the extra warmth and our Renanthera imschootiana will be flowering for a second time this summer which has never happened before.


365 days of orchids – day 574 – Dendrobium nobile ‘virginalis’

Dendrobium nolile is one of our favourite species and this week we have the pure white form in full flower. The more usual colour form is shown below.

The plant here flowering near Gangtok in Sikkim shows the natural growth habit. The plant grows long upright pseudobulbs during the warm wet summer months. In their second year these bulbs become less upright and produce heavy flowering in April. In their third year the bulbs are pendulous and produce a few extra flowers and by this time they have lost all their leaves.

The wild plants in Sikkim show a wide range of colour forms and one tree in particular demonstrated the variability of the species with dark forms, light forms, rounded flowers and more pointed flowers but we have yet to find the pure white var.virginalis. (see below) The tree also shows the habitat clearly with plants growing in dappled shade from tall trees and a little moss on the trunk showing that the dry season is far from bone dry here. In fact we found that it rains every few days in the dry season at this altitude 1200m. In cultivation we grow the species in Cool Asia with a minimum of 10C in winter and vents open above 17C. We keep the plants wet in summer and damp in winter, never allowing bulbs to shrivel.

Dendrobium nobile in SikkimThe species is found across a wide range in the Himalayas through to South East Asia. In Arunachal Pradesh (the extreme North Eastern state of India) we have seen the species growing on trees and on rocks as well as fallen plants used to adorn Buddhist temples and gompas. (below)

One of our plants is a real specimen and flowered to its full potential in 2013 when it won a Cultural Certificate from the RHS and produced one of my favourite orchid project photos. The plant may be even better than this next year as it is full of flowering potential now that it has become settled in its larger basket.