December  2,  1897. 
JOURNAL  OF  HORTICULTURE  AND  COTTAGE  GARDENER, 
52?> 
ERYTHTIONIUM  REVOLUTUM, 
Thkre  are  many  Erythroniums  in  cultivation  in  gardens,  and  several 
of  them  are  very  charming,  with  their  attractive  flowers  and  handsome 
leafage.  Erom  time  to  time  these  are  exhibited  at  various  shows,  while 
occasionally  rarer  ones  are  also  seen.  Amongst  these  latter  may  be 
classed  Erythronium  revolutum,  which  was  staged  at  the  Drill  Hall  on 
April  13th  of  this  year  by  Messrs.  R.  Wallace  &  Co.,  Colchester.  The 
plant  is  a  native  of  California,  and  is  said  not  to  have  flowered  in  this 
country  prior  to  the  time  of  its  exhibition.  As  may  be  seen  from  a  glance 
at  the  illustration  (fig.  77),  the  plant  is  well  named.  The  colour  of  the 
flowers  is  white,  delicately  flushed  with  rose.  The  Floral  Committee  of 
the  Royal  Horticultural  Society  awarded  it  a  first-class  certificate  on  the 
occasion  indicated. 
SWEET  PEAS. 
{Continued  from  'page  51.3.) 
Before  I  come  to  the  cultivation  and  the  selection  of  what  I  consider 
the  best  varieties,  I  should  like  to  say  something  on  the  fertilisation  of 
the  Sweet  Pea.  It  may  be  said  they  are  never,  or  very  rarely  indeed, 
fertilised  by  insects,  though  not  because  bees  and  other  insects  do  not 
visit  the  flowers,  or  that  they  never  collect  pollen  or  honey  from  them. 
In  the  case  of  the  Sweet  Pea,  and  I  think  I  may  in  dude  the  culinary  Pea 
and  many  others,  of  what  are  called  papilionaceous,  or  butterfly  flowers, 
fertilisation  takes  place  before  the  flowers  open,  so  that  it  is  impossible 
for  either  insect  agency  or  the  wind  to  have  any  effect  on  the  essential 
organs.  That  fertility  does  take  place  before  the  flowers  open  can  easily 
be  proved  by  opening  a  flower  bud  a  d  ly  or  two,  or  perhaps  two  or  three 
days,  before  it  expands,  when  it  will  be  found  that  the  anthers  have 
discharged  abundance  of  pollen,  and  that  the  stigma  cannot  help  being 
fertililised.  This  function  being  performed  in  the  flower  bud  has  not 
been  much  understood.  It  is,  indeed,  an  exception  to  the  general  rule, 
and  it  will  explain,  I  think,  the  reason  why  so  few  varieties  have  occurred 
up  to  a  comparatively  recent  date.  I  should  say  that  the  varieties  up  to 
twenty-five  or  thirty  years  ago  were  the  results  of  sporting  variations  in 
the  plant,  observed  and  perpetuated,  and  not  the  result  of  any  cross¬ 
fertilisation.  Artificial  fertilisation,  with  the  object  of  obtaining  new 
varieties,  must  be  done  with  great  care.  The  flower  bud  has  to  be  forcibly 
opened  and  the  anthers  removed  before  they  discharge  their  pollen,  and 
the  foreign  pollen  introduced.  It  requires  some  experience  to  know  the 
exact  time  for  this  operation. 
A  papilionaceous  or  butterfly  flower  has  five  petals  ;  the  upper  and 
largest  one  is  called  the  standard,  the  two  side  ones  the  wings,  and 
the  two  lower,  often  united,  form  the  keel.  These  fold  one  over  the 
other  so  beautifully  that  they  completely  shut  out  all  insect  agency 
until  the  flower  has  expanded,  when  a  bee  can,  by  settling  on  the  wings, 
prise  or  press  out  into  view  the  anthers  and  stigma,  and  so  collect  pollen  ; 
but  the  function  of  fertilisation  has  already  been  done.  It  has  been  said, 
and  I  am  not  going  to  say  that  it  is  not  true,  because  I  believe  as  a  rule 
it  is  true,  that  there  is  more  potency  in  foreign  pollen  than  in  own  pollen 
— that  is,  pollen  brought  from  one  flower  of  the  same  species  and  applied 
to  the  stigma  of  another  flower  of  the  same  species,  is  more  effective,  and 
further,  that  benefit  has  been  derived  from  crossing  between  individual  or 
separate  flowers  on  the  same  plant. 
Yet  it  is  worthy  of  remark  that  the  variety  Painted  Lady  Sweet  Pea 
has  been  known  for  at  least  a  hundred  years,  and  that  its  constitution  is 
equal  in  vigour  now  to  many  of  the  newer  varieties,  and  yet  it  has  all  this 
time  been  fertilised  exclusively  by  its  own  pollen.  Sir  .Tohn  Lubbock 
says  in  his  interesting  book,  “British  Wild  Flowers  in  Relation  to 
Insects,’’  that  it  is  probable  that  all  flowers  which  have  an  irregular 
corolla  are  fertilised  by  insects.  Now  we  all  know  that  the  Sweet  Pea 
has  the  most  irregular  of  corollas,  and  Darwin  says,  “  Everyone  who 
has  studied  the  structure  of  papilionaceous  flowers  has  been  convinced 
that  they  are  specially  adapted  for  cross-fertilisation,”  and  then  goes  on 
to  say,  “The  case  of  Lathyrus  odoratus  is  curious,  for  in  this  country  it 
seems  invariably  to  fertilise  itself.”  Darwin  does  not  think  the  flowers 
are  fertilised  at  an  early  stage.  He  acknowledges  that  the  anthers 
discharge  their  pollen  in  the  bud,  and  that  it  adheres  to  the  viscid  stigma, 
yet  he  found  the  pollen  tubes  were  not  exserted.  Darwin  is  inclined  to 
believe  that  with  oth6r  and  larger  insects,  such  as  may  exist  in  the 
original  home  of  the  Sweet  Pea,  the  flowers  would  intercross,  and  he 
quotes  the  airthority  of  an  Italian  professor,  who  says  “That  it  is  the  fixed 
opinion  of  gardeners  there,  that  is,  in  Sicily,  that  the  varieties  do  inter¬ 
cross,  and  that  they  cannot  be  preserved  pure  unless  they  are  sown 
separately.”  I  may  say  we  grow  a  collection  in  their  separate  colours  in 
the  immediate  neighbourhood  of  six  or  eight  hives  of  bees,  and  have 
never  had  the  varieties  mixed  in  the  slightest  degree. 
Respecting  the  seed  of  Sweet  Peas,  there  are  a  few  peculiarities 
worthy  of  note.  White  flowering  varieties,  as  well  as  the  primrose 
coloured,  have  seeds  of  a  light  colour,  with  the  exception,  I  ought  to  say, 
of  Mrs.  Sankeyq  which  is  dark.  This  is  curious  ;  but  as  this  variety 
has  a  tendency  to  become  tinted  it  may  explain  the  anomaly.  Again, 
we  have  several  varieties  of  pale  blue  and  kindred  shades  which  have 
somewhat  small,  wrinkled  seeds.  When  I  have  sent  these  varieties  away 
with  others,  I  have  more  than  once  been  told  that  certain  kinds  were  old 
and  no  good.  To  expose  my  own  ignorance  :  when  I  had  the  wrinkled 
seed  for  the  first  time  (I  think  it  was  Countess  of  Radnor)  I  did  not  like 
to  sow  it  with  the  other  kinds  in  case  there  should  be  a  blank  ;  so  I 
sowed  it  by  itself,  and,  of  course,  it  grew  as  well  as  the  others.  I  have 
sown  five  or  six -year-old  seed,  and  if  a  little  slower  to  move,  it  turned 
out  almost,  if  not  quite,  as  well  as  that  obtained  the  previous  year.  In 
picking  the  pods  for  seed,  whi6h  is  generally  done  when  the  pod  is  brown, 
it  is  a  mistake  to  shell  the  seeds  at  once,  as  they  are  not  often  at  this 
stage  thoroughly  matured.  They  should  be  kept  in  a  dry  place  for  a 
time  and  shelled  later,  when  they  will  be  thoroughly  ripe. 
In  the  cultivation  of  the  Sweet  Pea  several  methods  have  been 
suggested.  Some  recommend  sowing  in  trenches,  like  Celery'  ;  but  this, 
I  think,  should  only  be  adopted  when  the  soil  is  very  shallow,  sandy,  or 
gravelly.  We  heavily  manure  and  trench  our  ground  in  the  autumn,  and 
never  grow  them  two  years  in  sucession  in  the  same  place.  We  always 
select  a  good,  open,  and  prominent  position  for  our  collection  of  named 
varieties,  and  have  them  in  short,  6  feet  rows  with  walks  between  each 
series  of  rows.  As  our  collection  numbers  about  100  varieties  it  occupies 
a  considerable  space,  and  this  spot  is  more  visited  during  the  Sweet  Pea 
season  than  any  other  part  of  the  garden. 
Our  two  earliest  rows  of  Sweet  Peas  are  generally  mixed,  and  sown 
in  boxes  early  in  February  and  transplanted  when  ready  in  the  same 
way  as  the  garden  Pea.  Our  general  collection  we  sow,  if  the  ground  is 
Fig.  77.— Erythronium  revolutum. 
in  good  working  order,  the  first  week  in  March.  For  the  drills  we  use 
a  6-inch  flat  hoe,  and  make  them  about  3  inches  deep.  It  is  easier  to 
distribute  the  seed  in  a  drill  6  inches  wide  than  in  one  drawn  only  with 
the  corner  of  the  hoe.  We  almost  always  sow  too  thickly  ;  3  inches 
apart  is  quite  near  enough  to  produce  the  best  results.  I,  in  common 
with  most  others,  sow  more  thickly.  In  the  case  of  the  Sweet  Pea  it  is 
somewhat  excusable,  for  we  have  in  view  the  probable  depredations  of 
our  three  great  enemies  — birds,  mice,  and  slugs.  With  the  greatest  care 
we  frecjuently  have  them  gappy  and  patchy,  and  have  often  to  trans¬ 
plant  from  the  thicker  places  to  make  up  the  vacancies.  To  prove  that 
thin  sowing  is  better  than  thick,  the  new  kinds  that  come  out  are  expen¬ 
sive,  and  very  few  in  a  packet.  We  have  sown  these— or,  rather,  as  we 
generally  do,  transplant  them  from  pots — 4,  5,  or  even  6  inches  apart, 
and  they  always  make  the  strongest  rows  and  produce  the  largest  flowers. 
I  have  heard  on  good  authority  of  one  single  Sweet  Pea  plant  bearing 
200  fully  developed  flower-  stalks  at  one  time.  After  sowing  the  seed  we 
cover  it  with  about  2  inches  of  soil,  so  that  the  drills  are  left  a  little 
hollow. 
As  soon  as  the  seedlings  are  through,  we  draw  the  soil  up  on  each  side 
of  the  drills,  and  well  tread  on  both  sides.  This  is  strongly  recommended 
by  Mr.  Eckford,  and  should  be  repeated  several  times,  and  to  a  distance  of 
18  inches  on  each  side  of  the  rows.  This  is  considered  so  important  in 
America,  where  the  Sweet  Pea  is  exceedingly  popular,  that  they  call  it 
“  Firming  the  soil.” 
The  staking  is  generally  done  by  one  man  who  understands  the  work. 
A  little  brushwood  is  first  put  along,  then  the  stakes  to  the  desired 
height.  In  some  seasons  they  grow  much  higher  than  in  others.  When 
very  hot  and  dry,  especially  in  sandy  or  gravelly  soil,  they  become  stunted 
