Temperate or Subtropical Aussie? What are your normal lows?

Specifying where you are would certainly help. Are you equatorial, tropical, sub-tropical or temperate? For the most part outside would be okay, even in Melbourne they're okay outdoors. But in a temperate climate they'd grow a bit faster in the greenhouse.

if truly 'Sago Palms' (which they are obviously not) then there is no place in Australia where it would cold enough to have to put them in a greenhouse... but these are not Cycas revolutas, but some other species of cycas... if you live in northern Australia, they will be fine all year round, but as mentioned, will still grow faster in a greenhouse.

I live in Victoria which is Zone 3 in Australia...

The lowest temps would get is about 0 dg.

Palmbob,

Why do you say they are not Sago Palms? I am new at this but I when I was sold these seeds, they were sold as Sago palms, very expensive, lol.

I would be curious too as to why they're not (purely for personal, educational reasons). That said, do I see spines at the base of the two fronds of the one on the bottom-left? If so, then I would agree they're not sago (though I only have King Sago and not Queen). If those are spines, perhaps they are a type of Phoenix?

I'm guessing you mean 0C and not 0F (and looking at Australian gardening zones seems to confirm that). Here in my neck of Florida, we can sometimes see similar lows and my potted King Sagos manage it just fine with little protection as do my Coontie seedlings. Queen Sago would not handle that kind of low, at least not from the info I've read on them. If the above plants turn out to be Phoenix it could go either way. My Phoenix roebelinii get hit pretty hard when we get freezing temps. They survive, but they don't look good afterwards.

Hope to hear more as to why they're not Sago and possibly figuring out just what they might be. The idea that you might have payed for expensive seeds that turn out to be something other than what you ordered bothers me, though it has happened to me before as well.

The OP looks to be growing the true sago palm, Metroxylon sagu, which is not a cycad that many are accustomed to seeing.

Thank you all so much for your comments. I hope they survive so I can put the pics up to see what they end up being....lol

It is true that Aussies seem to have access to more Sago's than I have seen in Florida, even at the few Botanical Gardens I have been to. I enjoy watching the show Gardening Australia and I remember Costa, I think, doing a verge planting and putting in a 'Sago' that looked like nothing I had ever seen here.