Phacelia
sericea is a member of the Hydrophyllaceae, the
Waterleaf family. Other genera within the family of interest
to rock gardeners include Hesperochiron, Nemophila, and
Romanzoffia. Phacelia is by far the largest genus in the
family with about 200 species, most of which are annuals,
and few of which are suitable rock garden subjects.
Phacelia sericea is an
outstanding exception, a very attractive alpine within the
height limits appropriate for the rock garden.
Phacelia
sericea is native to most of the mountains of western
North America with the Yukon and Alaskan
Phacelia mollis sometimes
considered to be within Phacelia
sericea. A number of local varieties and subspecies
have been defined; however, apart from differences in
stature, the variation is of little consequence to the rock
gardener. Although plants from lower altitudes may be as
tall as 18 " (45 cm) in bloom, most alpine forms are under
4" (8 cm) out of bloom and under 10" (25 cm) in bloom. Its
leaves may be as long as 4" (10 cm), lobed, and covered with
silky hairs, giving a gray-sliver effect. The small flowers
appear to be all attached to a central vertical stem,
although they come from groups of stems attached to the
central vertical stem, making a solid 4 - 6" (10 - 15 cm)
vertical cylinder of blue-purple flowers.
Phacelia
sericea requires a very well-drained gritty soil and
a great deal of sun without subjecting it to too much heat.
In the Northern Hemisphere it should be planted on a north
facing slope to allow for full sun without getting the heat
of too much sun hitting the ground. It should be watered
sparingly during periods of drought.
Phacelia
sericea is propagated by seed which require a cold
(~40 F), moist period of 3 months before the temperature
rises to normal spring highs.
Meetings
December
2003
Phacelia
sericea is native to most of the mountains of western
North America with the Yukon and Alaskan
Phacelia mollis sometimes
considered to be within Phacelia
sericea. A number of local varieties and subspecies
have been defined; however, apart from differences in
stature, the variation is of little consequence to the rock
gardener. Although plants from lower altitudes may be as
tall as 18 " (45 cm) in bloom, most alpine forms are under
4" (8 cm) out of bloom and under 10" (25 cm) in bloom. Its
leaves may be as long as 4" (10 cm), lobed, and covered with
silky hairs, giving a gray-sliver effect. The small flowers
appear to be all attached to a central vertical stem,
although they come from groups of stems attached to the
central vertical stem, making a solid 4 - 6" (10 - 15 cm)
vertical cylinder of blue-purple flowers.