Yellow Leek Orchid - slow to flower this season

Yesterday, when commenting upon how "regular" in flowering time are the Liliums I grow, I made a rash promise to discuss the late flowering of some species of orchids. Already I have had my Orchid colleague, Colin Rowan teasing me about that promise. Well, for what it is worth, here it is.


I am going to discuss the Prasophyllum flavum - the Yellow Leek Orchid. As PlantNET says, it flowers from October to January.

Small plant of Prasophyllum flavum

I have seen this Orchid flower, in Penrose, here the Highlands, in the first week of November, over several years. Consequently I took that to be the "normal" flowering time at this altitude. 

Prasophyllum flavum - Yellow Leek Orchid

Several weeks ago I found a number of these plants flowering beside Tourist Road, in Kangaloon, along with Hyacinth Orchids, which are a normal summer-flowering species. This was the first time I have seen this species in that area - a fact I put down the the good rain we have had this year.

Prasophyllum flavum - the Yellow Leek Orchid

Then two weeks ago my friend Kirsten found the first of a number of Yellow Leek Orchids when we were looking for other plants along Belmore Falls Road. This area is a wet Eucalypt forest, with dense Proteaceous shrubbery as understorey growth. I was surprised to find these Orchids here, as I have often looked in this area, but never seen these Leek Orchids here, before. 

A tall flowering stem of Prasophyllum flavum

So, is this bold season of flowering of this Yellow Leek Orchid in the Robertson area related to the weather? And are these plants ones which would either not have flowered in drier years, or is it just that they have flowered so freely this year that they have become much more obvious than in previous years?


I cannot offer definitive answers, but I do know that there are closely related plants in the local area (other Prasophyllum species), which flower "like clockwork" in late October and the first two weeks of November. Why is this species suddenly flowering now? It is very tempting to say it is related to the rainfall. 


The best I can do is make the suggestion, and offer to monitor these plants over coming years.