This poem's title foreshadows its major meaning. "A Poison Tree" is the title of the poem, and towards the conclusion, a "foe" sleeps "outstretched under a tree" (16) after eating the (potentially poisoned) apple that grows on it. The poison tree can be interpreted as a metaphor for what occurs when you are angry for an extended period of time. Isabella Bird, in her book Mid-Victorian Britain, comments on this same idea, saying that "an apple a day keeps the doctor away."
In addition to this meaning, there is also a symbolic reference being made here. In the poem, the sleeping man represents evil, which has been prevented from doing any more harm by keeping it locked up inside him. The tree, however, is dangerous because it releases its venom slowly through its leaves and seeds; thus, preventing it from killing anyone immediately but making it able to cause much damage over time.
Finally, the tree itself is also seen as a symbol of evil because of how it takes pleasure in causing pain to others. Isabella Bird again comments on this idea when she says that the poison tree is "evil with delight in tormenting others."
Thus, "a poison tree" is a metaphorical name for someone or something that causes harm out of anger. The original poem itself is a fairy tale written by Christina Rosetti. It was published in 1881 along with another of her poems, "The Lost Child".
The apple has numerous connotations in "The Poison Tree," indicating "wrath," "temptation," and "deception." The poem's narrator talks about harboring a grudge towards an opponent who has hurt him. Rather than facing his adversary, he hid and nursed his resentment. This poisoned mind caused him to make terrible decisions, such as killing another person. His wrongdoing was compounded by the fact that some people called him "a murderer."
The apple also symbolizes temptation. The narrator describes how the devil came to him in the form of an attractive woman and offered him knowledge and wisdom. She would have done well to know him not because he was evil, but because he was human. He was capable of making choices just like anyone else. If he had listened to her, he might never have discovered his own strength or found salvation.
Finally, the apple represents deception. When the narrator looks into the mirror, he sees a handsome man who seems to have it all. However, when he glances over his shoulder, he sees that there is actually something wrong with him. His true appearance is hidden under a mask. He doesn't realize this at first, but once he does, he can no longer look at himself in the mirror.
One lesson of "A Poison Tree" is that if you hold onto your anger and fuel it, it will grow and damage someone—in this poem, it hurts an adversary, but it may also hurt the one who is furious. The poem is a long metaphor in which rage is compared to a tree. The tree can either be seen as poisonous or beneficial, depending on how you view it. If you see it as poisonous, then it shows that even though poison trees don't necessarily mean death, they can still be very harmful.
Another lesson from this poem is that hatred only grows over time. It starts out small and seems like nothing serious, but the more you think about it, the more you can see how important it is. This goes for people's feelings as well as trees' feelings when they are attacked. The angrier you get, the more damage you do to yourself and those around you.
Finally, the poem teaches us that there are many ways to handle something difficult. You can lash out at someone, let it consume you, or embrace what is meaningful and good about life. All things considered, holding onto your anger didn't do anyone any good. It may have caused some trouble for others, but not killing someone would have done that too. Embracing what is good about life helps put everything in perspective and gives you strength you need to move forward.