Though there numerous types of forget-me-not, there are two varieties that seem most likely to correspond with Tolkien's intentions. The Water Forget-me-not Myosotis scorpioides thrives in watery conditions, and given the connection of these flowers to the River-daughter of Withywindle, this is probably the most plausible candidate. The Wood Forget-me-not Myosotis sylvatica prefers ancient woodland, so might also have been expected to grow in the Old Forest near Tom Bombadil's house. These two varieties are very similar in appearance, but the Water Forget-me-not has flowers of a slightly paler blue, with more rounded petals, than its woodland counterpart.

There are numerous tales and myths around the origin of this flower's name, to the extent that a definitive explanation is probably impossible to achieve. Tradition has linked this flower to undying and unforgotten love for centuries, and this tradition seems to have originally taken root in Germany. By about the year 1400, 'forget-me-not' had entered the English language as a literal translation of the German name Vergissmeinnicht.

The meaning of this flower's name is almost identical to that of simbelmynë or Evermind that grew in Rohan, but this fact does not seem to carry any deep significance. The simbelmynë flower is described as being similar to an anemone, and therefore quite different to the common blue forget-me-not.