View source for Roscoea

{{SPlantbox
|familia=Zingiberaceae
|genus=Roscoea
|Min ht metric=cm
|Temp Metric=°F
|jumpin=This is the plant information box - for information on light; water; zones; height; etc. If it is mostly empty you can help grow this page by clicking on the edit tab and filling in the blanks!
|image=Roscoea purpurea 20070810-1338-183.jpg
|image_width=180
|image_caption=R. purpurea
}}
'''''Roscoea''''' is a genus of [[perennial plant]]s of the family ''[[Zingiberaceae]]''. They are native to [[China]] and [[Himalayas]] and related to a [[ginger]] plant. The ''Roscoea'' flowers resemble an [[orchid]]. There are 18 species in this genus.<ref name="Botanica 801">"Botanica. The Illustrated AZ of over 10000 garden plants and how to cultivate them", p. 801 Könemann, 2004. ISBN 3-8331-1253-0</ref> 

{{Inc|
Roscoea (named after Wm. Roscoe, 1753-1831). Zingiberaceae. Half-hardy perennial herbs often grown in the warmhouse, but also used for border planting.

Roots thick, fleshy, and fascicled: lvs. lanceolate or oblong: infl. in terminal spikes; bracts persistent, 1-fld.; fls. purple, blue, or yellow; calyx long, tubular, slit down one side; corolla-tube slender, lateral segms. spreading, upper broad, cucullate, erect; lateral staminoides oblanceolate, petaloid, erect, lip large, cuneate, deflexed, 2-cleft or emarginate; ovary 3-celled: caps, cylindric or clavate.—About 15 species, Himalaya region and China. Roscoeas thrive in light turfy loam and are prop. by division. R. purpurea is the species best known in cultivation.
}}


==Merge this info==
Info from: Robert Hamilton

Roscoea  is a  small genus  of late  spring / summer  growing   plants of the  ginger  family ,  Zingiberacea.  They  have  a  growing  point from which a  cluster  of thickened  roots decend ,  somewhat  like  a Dahlia  but   in minature  form.  The leaves are reminiscent of a minature  sweet corn, with  flower  at  the apex , which  to  my  eye is  somewhat  orchid like (thinking  Masdevallia)  with one  large decending  petal  and  several smaller petals  above  and  beside the main  petal. They  originate  mainly from India,  Nepal  and  China.

In  Tasmania they  need  partial  to  full  shade   and   additional summer  watering  to  grow  well.  They  tolerate  moisture  when dormant  and  do  equally  well in the ground or  pots. For  those  in cooler  climates  they  are  said  to  be outdoors hardy in Britian.

They  germinate  easily  from  seed . When sown in late summer germination  usually occurs in autumn,  while  seed sown in early spring  emerges with the timing of  mature  plants. Some  species tend to  seed around  a  bit  including into  adjacent  pots. Mature  plants can  be  divided in  winter.

The biggest  problem with Roscoea is  identification  of the species. Several  species  have  been perpetually misnamed  . The best  treatment

I  have  read of the  genus  is  by Richard  Wilford from  RBG Kew in the March 1999 quarterly  bulletin of the Alpine  Garden  Society.

I  grow  the  following   but  cannot absolutely guarantee the  identity of  my  species.They range  from 5cm (2 inches )  to  30cm (12 inches) tall.

Roscoea  alpina  -  a  small  species with  mauve to  purple  flowers which  is  easily  grown  and  seeds  freely.

Roscoea australis  -  small  purple /  mauve  flowers  similar  to alpina  but  has broader  and  shorter  leaves.

Roscoea auriculata - this plant  has been distributed in  Australia as 

Roscoea purpurea or purpurea procera. It  grows  well  but does  not tolerate  too much  sun - I  often  find it  wilting  after a warm  day, but it   recovers  with a  good water in the  evening. Flowers  are a deep violet-purple. The auriculata  refers  to the ear shaped first leaf on the pseudostem.

Roscoea cautleoides - in its  yellow   form it  is easily  recognised but  purple  and  white  forms  are  becoming available with the explosion of  new plant  material  from  China.  I  find it needs  help to  set seed  and the  seeds are difficult  to recover from  amongst the bracts.

Roscoea humeana - this  has a  large  hooded dorsal petal  , larger than  the  labellum giving it a distinct appearance. It  is  commonly 
purple  , but  yellow  , cream  and  white  forms do  occur.  My seedlings  are  reasonably  new but  it  seems to  be  a vigorous grower.

Roscoea purpurea  - this  is  the  type  species  which  was  described in  1806.  Flowers  are pale  purple  or  mauve. It  is  said  to  be the most  vigorous  species  growing up  to  50cm  ( 20 inches )  tall.

I  have  kept  my  original  plant in a  pot  and  have  not  found it to  be this  vigorous, but it  has quite  broad  and  heavy  leaves.  I intend  to plant  in the  garden  next  spring  as  I  now  have  my own  seedlings . To illustrate the difficulties  with identification I have now  almost  convinced myself  that my plant  is  R capitata - my plant  has  flowers of  rich deep  purple on a long peduncle- seen the image.
A red form  of R purpurea  was  discovered in 1994 a unique  colour in the  genus.

Roscoea scillifolia- this  is  the  smallest  of the  genus  growing little  more than a  few  cm tall. The  flowers can  be  pink  , purple or  white. I  have a pink  form whose  flowers are  fairly  fleeting. It  seeds  around   quite  freely  and  appears last of the  species I grow - in flower   at  present  in early February.

Roscoea tibetica - my  plants  are  still unflowered seedlings. It is another  small species  with  typically  dark purple  flowers , which can  also  range  from violet  to  mauve , rose or  white. The photograph in the  AGS  article  shows  horizontal  lateral  petals making it look  more like a  typical  orchid  flower.

The  following list  of  species  I  have  not grown is  taken  from the  AGS article.

Roscoea Beesiana  - a  vigorous  hybrid  between auriculata and cautleoides with variable amounts  of violet striping.

Roscoea capitata -rich  deep purple

Roscoea forrestii- small  , yellow  or  purple  flowers.

Roscoea ganeshensis - a  recently  discovered  species  from Nepal. Pale  purple  flowers , with  narrow  dorsal petal  is a   paler colour than the rest of the  flower.

Roscoea praecox - a  new  species  collected on the Alpine Garden Society China  Expedition. Purple   with  up to  six white  lines on the base of the  labellum.

Roscoea schneideriana - dorsal is  pale pinkish -purple  with rest of the  flower a  darker violet-purple.

Roscoea tumjensis - dark  purple  similar  to  humeana with  labellum larger than the dorsal  petal.

Roscoea  wardii - purple   flowers.

I have posted  some Roscoea to the wiki which  I  have  dragged out of  my archives -  none  are  photographic masterpieces but  give  some idea  of the species available.

http://www.ibiblio.org/pbs/pbswiki/index.php/Roscoea

Roscoea alpina -  sorry  I didnt  remove the  dead  flower.

Roscoea auriculata makes an  attractive  small clump.

Roscoea capitata - obtained as   seed  as R purpurea but my  =93homework=94= makes  me think this  is  the correct name - in reality  it is a  rich deep purple.

Roscoea cautleoides- the  colour is  a little  washed out on this  image Roscoea humeana -the split dorsal  petal  is  not a normal  feature but the image illustrates its =93fuller =93 flower.

Roscoea ?Beesiana- this  is  Lyn=92s  image of  a plant  she obtained as = R cautleoides which  we think  may be the  hybrid  R Beesiana, said  to  have variable  violet  striping.

==Cultivation==


===Propagation===


===Pests and diseases===


==Varieties==
Some species:
* [[Roscoea cautleoides]]
* [[Roscoea humeana]]
* [[Roscoea purpurea]]

==Gallery==

<gallery perrow=5>
Image:Upload.png| photo 1
Image:Upload.png| photo 2
Image:Upload.png| photo 3
</gallery>

==References==
<references/>
*[[Standard Cyclopedia of Horticulture]], by L. H. Bailey, MacMillan Co., 1963
<!--- xxxxx  *Flora: The Gardener's Bible, by Sean Hogan. Global Book Publishing, 2003. ISBN 0881925381  -->
<!--- xxxxx  *American Horticultural Society: A-Z Encyclopedia of Garden Plants, by Christopher Brickell, Judith D. Zuk. 1996. ISBN 0789419432  -->
<!--- xxxxx  *Sunset National Garden Book. Sunset Books, Inc., 1997. ISBN 0376038608  -->

==External links==
*{{wplink}}

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