Sunday, December 25, 2011

Merry Christmas and Happy New Year from the Pitcher Plantation

Drosera arcturi, Cradle Mountain N.P.
Well, it may not be a white Christmas here in Australia, but here is an alpine plant in honour of the season. These are Drosera arcturi, photographed at a tarn lake high on the alpine plateau in Cradle Mountain National Park, Tasmania. This tarn lake was a few hundred metres from the slopes of Cradle Mountain itself.
Drosera arcturi, Cradle Mountain N.P.2
These plants are growing in Sphagnum peat between the branches and leaves of a cushion plant (the moss-like plant growing right up to the edge of the tarn lake).

Sunday, December 11, 2011

Sarracenia rhizome rot (and fertiliser burn) – how to recognise and treat it

****June 2013 Edit – Important Information****

The cause of the rot shown here is not fungus. After a long process of elimination, some plant pathologist colleagues determined the cause is most likely fertiliser burn. While fertilisers (I used slow release fertiliser here) are useful for getting seedlings up to size, overdoing the dosage can induce symptoms similar to a plant affected by rhizome rotting fungi – wilting pitchers, dead rhizome tissue and death shortly afterwards. These symptoms are caused by the roots being burned by the fertiliser and reducing water flow through the plant. In plants infected with fungi, the infection kills the tissues transporting water through the plant, producing much the same outcome.

For reference – this case involved a mature Sarracenia flava var. cuprea in a 140 mm pot. I had fertilised it with around 12 pellets of slow release fertiliser the previous spring.

The recommended dose of slow release is 4 pellets or less per 100 mm/4” pot.

Aside from the different cause, the information below is correct for the symptoms, and applies equally to fungal rots and, obviously, fertiliser burn.


****Amended original post****

I had a very nasty surprise last week – several of my best Sarracenia flava clones started wilting, even though they were sitting in trays of water. I have seen this before in Sarracenia that have not been divided often enough. You should dread this type of symptom, because it means you are on the verge of losing your plant and must act immediately.