This herbaceous perennial plant is 3-9" tall, branching frequently and
forming a mat. The stems have a tendency to sprawl; they are light
green to reddish purple, terete, and pubescent. Pairs of opposite
leaves occur at intervals along these stems; clusters of smaller leaves
usually develop from the axils of opposite leaves, causing them to
appear whorled. The leaves are ¼–¾" long, 1-2 mm. across, linear in
shape, and green; their margins are entire (toothless) and sometimes
Because the leaves either clasp the stems or they are sessile, petioles
do not occur. Either solitary or small cymes of 2-8 flowers occur at
the tips of stems on short pedicels. The pedicels are light green or
reddish purple, terete, pubescent, and up to ½" long.
The corollas of
the flowers are ½–¾" across and almost as long; they have narrowly
tubular bases and 5 spreading lobes that are oblanceolate in shape and
slightly to moderately notched. The corollas are purple, lavender, rosy
pink, pink, white, or bicolored. The calyces are about ¼" long, light
green to reddish purple, short-tubular with 5 slender teeth, and
pubescent. Inserted within the narrow throat of each corolla, there are
5 stamens and a pistil with a single style. The hairs of the foliage
and calyces can be glandular or non-glandular (usually the latter). The
blooming period occurs during mid- to late spring for about 3-5 weeks.
Afterwards, the flowers are replaced by small 3-valved seed capsules
that are about 4 mm. long. Each capsule contains 3 or more seeds. The
root system is fibrous. This plant spreads by reseeding itself. The
foliage is semi-evergreen.
The preference is full sun, sandy or rocky soil, and dry conditions.
This plant will adapt to ordinary garden soil containing loam, but good
drainage is important.
Range & Habitat:
populations of Moss Phlox occur in widely scattered areas of Illinois,
including the NE section of the state (see Distribution
they are rare. Moss Phlox is native to the Appalachian mountains. This
plant is often cultivated in flower gardens, from which it can escape.
Habitats include sandy roadsides, sandy or gravelly areas along
railroads, and rocky bluffs. In the Appalachian mountains, this is a
conservative species that occurs on riverside outcrop prairies, shale
glades, limestone glades, serpentine barrens, and rocky ledges of
cliffs. It is not invasive in Illinois.
flowers attract butterflies, skippers, and long-tongued bees. Nectar is
the floral reward for these insects, although some of the bees also
collect pollen. Steury et al. (2009) observed a mason bee, Osmia
, visiting the flowers of Moss Phlox at a riverside
in Virginia. The foliage, flowers, and/or seed capsules of Moss Phlox
are eaten by some species of plant bugs (Miridae). This include 2
monophagous or oligophagous species, Polymerus tinctipes
, and 2 polyphagous species, Lopidea minor
A flower garden at the Urbana Free
Because of its low semi-evergreen foliage and attractive flowers, Moss
Phlox is often cultivated along the borders of gardens. Many cultivars
with differing flower colors have been developed and released to
members of the public. Moss Phlox can be distinguished from other Phlox
species by its narrow linear leaves and tendency to form low sprawling
mats of foliage. Whereas other Phlox species have pairs of opposite
leaves along their stems, the leaves of Moss Phlox usually occur in
clusters, causing them to appear whorled. Other Phlox species are
usually more erect with wider leaves; if secondary leaves are produced
from the axils of their opposite leaves, they are less abundant.