South African species - a growing passion

Satyrium bicallosum

This is one of the seldomly seen Satyrium species found in the Western Cape mountains. One of the reasons for this is because it is so tiny that most people would walk right past it without even noticing it. In addition it doesn't flower every year either. I have two colour variations in my collection, one completely white form or alba variety shown below and another more common colour variety with white and soft pink flowers (not flowering yet this year). I grow this species in a well draining mix of washed river sand, silica gravel (small grain) and palm peat fibre. This species is a little tricky because of its size and it often suffers if the potting mix is too deep, possibly because the deeper mix retains more water. Mine are potted in shalow plastic food tubs (only about 3-4cm deep). It enjoys good lighting but for some strange reason it is extremely phototrophic and the only way to get it to grow straight is to have its lighting manipulated so that it falls directly overhead. If not, the plant will bend towards the nearest strongest light source. This species is not to be confused with Satyrium bracteatum which is slightly bigger with similar shaped flowers. However, S. bracteatum flowers have a rather unpleasant smell while S. bicallosum is reported to have a cheese-like scent although mine don't smell at all. I recently used pollen from this species to attempt a hybrid with S. odorum. Hopefully I will get some viable pods in the near future.

My finger (for size reference!)
Satyrium bicallosum alba variety

Bonatea speciosa - from seed to flowering plant
Bonatea speciosa is undoubtedly one of my all-time favourites. It has the most captivating flowers and the scent from the blooms is intoxicating at night. This species is not yet available commercially in South Africa although it is not surprising that it is offered for sale by commercial growers occasionally in the US and Australia. I believe that in time this species will attract a lot more interest in South Africa as a local species to grow in the garden. I have increased my attention to optimising in vitro media for its optimal growth and propagation. I have raised a few seedlings of my own in vitro and in the process I have learned much about their growing requirements. This year (2013) I will be putting my final recipe to the test. Previously I sowed a couple of seeds on 9 December 2010 which I had purchased from one of the online vendors selling South African orchid seeds. The seeds were dry seeds from a dehisced pod so I subsequently surface sterilised them before plating them out on 1/2 strenth MS medium supplemented with 0.2% carbon and 10% coconut water. A few seeds germinated on 11 January 2011 and developed slowly for the first few months. Once the first shoots appeared the seedlings developed more rapidly. I potted some seedlings up on 3 August 2011 and hardened them off in the greenhouse for two weeks using a plastic tub to cover the seedlings to maintain high humidity. Seedling foliage was replaced by more general foliage within 6 months. Seedlings continued to develop well under greenhouse conditions until I moved to Hermanus. The seedlings continued to develop for another full season without any supplemented heating and finally bloomed successfully this September after approximately 970 days post germination.
Summary of stats for Bonatea speciosa from seed to first flowering (approximate):
Germination = 30 days
Potting up ex vitro = 234 days old
New set of foliage = 414 days old
First successful blooming = 970 days old

Bonatea speciosa germinating seeds
Bonatea speciosa differentiating protocorms
Bonatea speciosa shoot formation
Bonatea speciosa in vitro seedlings
Bonatea speciosa potted up
Bonatea speciosa F1 first flower front view
Bonatea speciosa F1 first flower side view

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