Den. Tosca ' Shiraz Ice' information
 

I am trying to sort out how to "winter" my dendrobiums. I have found help here, but I can't find anything, anywhere about my Tosca 'Shiaz Ice'. Does anyone know anything about it that can help me understand how to treat it this winter?

This hybrid is made up from a lot of species. Most of them in nature get a cooler and drier winter. Eliminate fertilizer and reduce watering until spring. Don't let it go without water completely but it can have less and maybe sit on a cool windowsill.

It is an 'Aussie' hybrid, with kingianum & many other species. No fertilizer from mid September fo April first. Cut back watering significanfly (once every 10-14 days) till flowers open. Then you can increase watering a bit.

In winter months: Cool & bright.

Something with kingianum in it needs a cool, no fertiliser and sparing watering over the winter. I like to stop fertiliser at the end of August (no biggie if you don't until later but they flower better for me if I stop then). I fertilise again from mid Feb.

I keep my kingianum hybrids in a cool greenhouse that is protected from frost but only heated to keep a min of 5C so a lot of the year is just whatever temp it is out there.

However some complex kingianum hybrids contain some warmer growing species and these can do quite well in the house all year. I have one called Berry 'Oda' which many people grow well as a house plant. I grow it out with my other kingianum hybrids going cool though.

Generally complex hybrids with parents from a range of different subsections of dendrobium can do well in a wider range of conditions. I haven't looked up the parents of yours, but if some of the parents are warmer growing it may do well either warm or cool. Personally even if it contains dendrobiums that can be fertilised all year I would still go with no fertiliser/less water over the winter, it's easy to do and won't hurt and may help.