My first impression of the poem was that its very negative and includes elements of destructin revenge and perhaps even murder. I think the poems about two lovers, one of which cheated on their partner and the other wants revenge.
The poem is very contradictory, this is shown in the first line “O Rose, thou art sick”. What is the rose? There are positive words associated with it, 'life' and 'joy'. Roses are symbols of love, of femininity, of beauty, of sexuality. The rose is also 'crimson', a very deep red which could suggest passion, or blood, or sin (as in 'scarlet woman'). It also has a 'bed' which is again, this could have sexual associations, or it could suggest being 'rooted' and passive.
Blake addresses the rose as a person. The effect of apostrophizing the rose is to add impetus and drive to the speaker's tone, creating a mood of alarm from the very beginning. A rose usually symbolises beauty, romance and love, it’s a very feminine image but then it is said to be sick so we instantly sense something is wrong. The rose could be damaged or hurt. I think the rose is playing the part of the woman and the worm is personified as the man. We are in no doubt that something is wrong and that something sad and worrying has happened. Blake could be talking about a real rose here, or using a metaphor for his society, which he may perceive as being damaged.
The vocabulary of the poem is also very simple. Blake has chosen to use basic words like 'storm' and 'night', the words which have simple meanings but also many associations. Think of all the things you associate with the word 'night', for instance, darkness, sleep, dreams, sex, and so on. The key to working out an interpretation of the poem is to look at the associations of the words. As you read it, think about and jot down what the words mean to you.
“The invisible worm”. The image of the worm is very unusual but yet very effective. Worms are seen as slimy, dirty and they feed on death, it even holds some kind of dirty and they feed on death, it even holds some kind of sexual element. He fact that the worm is invisible indicates it can’t be stopped and nothing can be done because it can’t be seen. The worm, by contrast, is active and seems entirely negative. It is also 'invisible', 'dark', 'secret'; it 'finds out' and 'destroys'. The worm is sneaky which is already invisible, it travels under the cover of darkness. It 'loves' the rose, yet its love is completely destructive.
Blake is inviting us to see the rose and the worm as symbols which is they must 'stand for' something but it is hard to know for certain what that something is. A common interpretation is that the rose represents beauty and innocence and the worm represents corruption and decay, all beauty must inevitably grow rotten. The collection of poems in which 'The Sick Rose' appeared, 'Songs of Experience', is full of images of innocence becoming corrupted and ruined. Alternatively, a feminist might see the rose as symbolising a woman and the worm a man, which destroys the rose's life with his oppressive 'love'. A religious reading might see the worm as being a close relative of the serpent in the Garden of Eden, corrupting the innocent beauty of humanity with original sin.
Any interpretation, though, will look at the use of opposites in the poem. The worm and the rose are opposites, the worm is invisible, fast-moving, destructive which is the rose is crimson, static, and joyful. They are in conflict as a result, the rose ends up being slowly destroyed. In conclusion, “The Sick Rose” uses fierce, moving words to create strong feelings as it concludes with death, grief and great emotional sorrow.