Rosette (botany)

In botany, a rosette is a circular arrangement of leaves, with all the leaves at a similar height.

Though rosettes usually sit near the soil, their structure is an example of a modified stem.

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.

Another kind of protection is provided by the caulescent rosette which is part of the growth form of the giant Espeletia genus in South America, which has a well-developed stem above the ground. In tropical alpine environments a wide variety of plants in different plant families and different parts of the world have evolved this growth form characterized by evergreen rosettes growing above marcescent leaves. Examples where this arrangement has been confirmed to improve survival, help water balance, or protect the plant from cold injury are Espeletia schultzii and Espeletia timotensis, both from the Andes.

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.

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