Hi, (I know this is a late reply but...)
I wouldnt' be able to memorise the whole poem, but more quotes that you know you can compare and use within the essay - but mostly the main ideas and themes that you can compare to ibsen.
This is great advice, I would definitely look at Goblin Market as there's a lot of comparisons you could make and it's a good one to bring in. Per essay, I would say you need 3 poems at least, so I would pick out poems that you know you can compare for each theme e.g. relationships - Nora and Torvald - Maude Clare etc.