Hi fellow Kiwis

I'm having a lot of trouble germinating seeds of the above. I obtained them back in June (quite legally) from NZ Tree Seeds, and have yet to see any come through! I've tried stratification, the boiling water treatment (ala Kowhais), but as yet with no success. Any tips? I used to grow them easily from cuttings back in NZ, and would love to grow at least one here. Similar story with seeds of the Nikau palm (Rhopalostylis Sapida), and the Northern Rata (Metrosideros Robusta). No success at all, though i've got happy seedlings of Lancewoods, Chatham Island Forget-me-nots, Kowhais, and Kaka-beaks. I would really appreciate any advice at all to help me get those troublesome buggers up and started!