Quote from : Spenser's Faerie queene: An interpretation Book

Now the twelfth canto of Book II is an almost literal translation from Tasso description in the Jerusalem Delivered of the island of Armida. That poem was not printed till 1582. It is likely enough that Spenser may have seen part of it in manuscript, which would account for the general resemblance of the Adonis passages, though the likeness is not close enough to make any debt certain.