Purple hyacinth beans or Lablab purpureus in Ottsville, Pennsylvania  [FX]
Purple hyacinth beans or Lablab purpureus in Ottsville, Pennsylvania  [FX]
D271-2012 Hyacinth Bean vine on a trellis.
Looking eastward through the hyacinth bean trellis toward the trellis against the knot garden wall.  I don't know what that vine is; I just know it's not a hyacinth bean vine.
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Toledo Botanical Garden, Ohio.
September 28, 2012
D271-2012 Hyacinth Bean vine on a trellis.
This large vine was laden with ripening beans, but was still producing blooms late into the autumn.
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Toledo Botanical Garden, Ohio.
September 28, 2012
D271-2012 Hyacinth Bean vine on a trellis.
Lablab purpureus is but one of the commonly used binomials for this species, and hyacinth bean is but one of a number of common names.   
A member of the family Fabaceae, it is widespread throughout the tropics.  Nearly all parts of the plant are edible when fresh, but the beans are toxic when dried unless subjected to prolonged boiling.  It is grown for its food value in Africa, among other tropical locations, but is raised for its visual interest and its appeal to hummingbirds in North America.
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Toledo Botanical Garden, Ohio.
September 28, 2012
Hyacinth Bean, Indian Bean, Lablab Bean, Lab-lab Bean, Poor Man's Bean, Tonga Bean, Banner Bean, Field Bean, Pig-ears, Calavance, Egyptian Bean, Njahi, Bulay, Bataw, or Selm (Lablab purpureus).
Purple Hyacinth Bean vine  -- Lablab purpureus
Scarlet Runner Beans
Purple hyacinth beans or Lablab purpureus in Ottsville, Pennsylvania [FX]
Purple hyacinth beans or Lablab purpureus in Ottsville, Pennsylvania  [FX]
Purple hyacinth beans or Lablab purpureus in Ottsville, Pennsylvania [FX]
See photo in original gallery.