Topic of the Week: Scilla ( and Hyacinthoides )
A genus with about 90 species, native of Europe across to the Far East
and with a number of African species. My experience in zone 8.
Probably best known and one of the hardiest of the short stemmed
inflorence with nodding flowers, the brilliant blue S. sibirica will grow in about
any position baring waterlogged or deep shady positions. The form 'Spring
Beauty' doesn't seem much different from the usual commercial form ( or they are
mostly SB in the trade ? ). A commercial white form has rather imperfectly
formed florets but is nice from a distance. The pale blue plant previously known
as S. sibirica var. taurica is apparently now S. ingridae-it is much less
vigorous here and does not spread as freely as I'd like. Paler yet , S.
mischtschenkoana (tubergeniana), is a very floriferous and valuable plant that
naturalizes well. S. m. 'Zwanenberg ' is slightly bluer in color. Much rarer and less
willing to increase by seed or bulb is the lovely S.melaina with mid-dark blue
flowers, a great favorite here as well as a bright mid blue plant collected
by Oleg Polunin and distributed as S. sp. Lebanon ( apparently NOT S.
libanotica). The most distinct of the group, S. rosenii bears reflexed tepals a la
Cyclamen; it supposedly prefers a dampish peaty medium, but grows here well
enough in a raised bed in well-drained soil.
Another group with taller inflorescence, more open flowers and a leafier
appearance includes the soft blue ( or white ) S. bithynica which self-seeds
rapidly in a half-shaded to shaded spot. Probably closely related but
apparently only found as a naturalized plant, S. amoena has darker flowers and is
better in a sunnier spot. Two others that have been much confused and good
also in shady position are S. hohenhackeri and S. greilhuberi. Scilla
greilhuberi puts out leaves in early autumn and bears 10 inch racemes of pendent blue
bells-it bears quite a few leaves- perhaps too many. Scilla hohenhackeri waits
until spring to sprout its neater leaves and is equal to greilhuberi in
beauty. Apparently closely related but with much narrower leaves S. griffithii is
rarely grown, seems to need a sunnier position and is worth seeking out. One
other that puts out leaves early in winter and often gets frosted here in zone
8, S.cilicica is best in pot/frame culture with nice soft blue flowers.
Another somewhat similar species, from Cyprus ( mountains ), S. morrisii flowers
in winter here with milky pale blue flowers. It hasn't been thorough a
rigorous winter here yet.
Other European taxa with outfacing flowers include S.verna, a diminutive
plant for the collector; a taller form has been distributed by the Archibalds
from the Pyranees. Scilla monophyllos with its nice upright raceme of bright
blue stands out by its single broad leaf; virtually identical in flower but
with more numerous and narrower leaves, S. ramburi has naturalized itself in
a sunny spots here. Another with much broader leaves, S. messeniaca will also
naturalize in ordinary garden beds. Somewhat similar, S.liliohyacinthus has
a bulb that mimics somehow a lily bulb; it does well in shade but didn't
increase much in a former garden. Much taller and with an airier inflorescence and
narrow leaves, S. persica naturalizes here easily and has good mid blue
flowers; though it comes from water meadows in Iran it grows well here without
summer watering. S. peruviana was discussed on PBS earlier this year.
A group with a few narrow leaves and racemes with up-facing flowers the
bright blue S. bifolia with its pink and white forms is rather well known and a
worthy plant for naturalizing. A very rare old form I'm fortunate to grow is
S. bifolia ' Praecox ' , a much stouter plant that increases excruciatingly
slowly; it has the look of a polyploid. At the other extreme is the tiny
snow-melt plant that has been called S. nivalis, frailer and much less carefree
than bifolia
For late summer/autumn S. scilloides (also incorrectly grown as
S.nubiensis, which is a distinct species from N. Africa ) leads the pack, usually
flowering in August with its pinkish-mauve flowers that are nice with Leucojum
autumnale. Closely following and with much more open racemes are forms of S.
autumnale with white, pale blue to dark blue flowers. It is borderline hardy
here and is a collector's plant. Following upon its heels is S.intermedia
another collector's only plant, followed in November-December by the excellent
lingulata with bright blue flowers. John Lohnsdale has recently enumerated a
number of forms he grows. It is a pot plant here, probably better in zone 9.
Although the wood squills or blue-bells are now widely offered under the
generic name Hyacinthoides (previously called Scilla or Endymion ),
distinguished from Scilla by the bulb being renewed yearly and having each flower
subtended by two ( rather than one ) bract. Brian Mathew told me once he considers
it part of the genus Scilla, since the anomalous bulb in the genus Scilla may
be analagous to the very different various bulb forms included in the genus
Ornithogalum. The tallest and broadest-leaved, H. hispanica has flowers
scattered around the stem. The smaller, narrower leaved and having narrower
flowers hanging in one side of the stem, H. nonscripta is less well known in the
US; it is the famous English blue-bell that forms such enchanting pools of blue
in copses and roadsides. These two hybridize easily in cultivation and in
Puget Sound where I live the hybrid, which has been distinguished as H. x
massartiana in Europe, is vastly more common in gardens than the parental species.
Two cultivars that I consider essential are the tall blue ' Excelsior ' and the
bright violet-rose-pink ' Dainty Maid ', both wonderfully effective in the
garden. There are several smaller species. Hyacinthoides italica has starrier
outfacing flowers on 6-8 inch stems among rather broadish leaves. It naturalizes
easily. Two others with similar but slightly smaller flowers but with narrow
leaves are H. reverchonii and H.vincentina ( the latter with a nice white
form), both only grown in a frame here so far.
Jerry John Flintoff
Vashon Island,Washington,USA
Zone 8