Yes, isn't that interesting? :-)
Τριαντάφυλλα είναι κόκκινα
Βιολέτες είναι μπλέ
Η ζάχαρη είναι γλυκιά και έτσι είσαι!
'That rose is red' am I wrong in thinking it should be?
Since "αυτό" means "this" it should be the main translation. However, in colloquial English "that" could also be used and I've added it.