Basal rosette

In botany, a rosette is a circular arrangement of leaves or of structures resembling leaves.

In flowering plants, rosettes usually sit near the soil, their structure is an example of a modified stem in which the internode gaps between the leaves do not expand, so that all the leaves remain clustered tightly together and at a similar height.

In bryophytes and algae, a rosette results from the repeated branching of the thallus as the plant grows, resulting in a circular outline.

Many plant families have varieties with rosette morphology; they are particularly common in Asteraceae (such as dandelions), Brassicaceae (such as cabbage), and Bromeliaceae. The fern, Blechnum fluviatile or New Zealand Water Fern () is a rosette plant.

Often, rosettes form in perennial plants whose upper foliage dies back with the remaining vegetation protecting the plant. Another form occurs when internodes along a stem are shortened, bringing the leaves closer together, as in lettuce and dandelion and some succulents. (When plants such as lettuce grow too quickly, the stem lengthens instead, a condition known as bolting.) In yet other forms, the rosette persists at the base of the plant (such as the dandelion), and there is a taproot.

Part of the protective function of a rosette like the dandelion is that it is hard to pull from the ground; the leaves come away easily while the taproot is left intact.

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