Foxglove

Foxglove was a wildflower of the digitalis family that possessed medicinal and poisonous qualities.
  Foxglove flowers were small bell-shaped buds of various colors, from red to lavender.
  Foxglove plants were known to spawn nightshades, elemental spirits of poisonous plants.
  Foxglove, like other flowers in the digitalis family was used as a tonic medicinal heart stimulant, and to treat kidneys. The latter medical use was also used as a poison. The plant's flowers were crushed and ground into a medicine extract, notably sweet to taste. The extract was used as a medicine in small doses, however if too much was consumed, the substance caused confusion, hallucinations, and eventually, heart failure.
  A special mystical potion of magical stasis was brewed using numerous rituals and components, including foxglove.
  Another powerful potion using foxglove was brewed in the days of ancient Netheril. The potion contains several deadly substances and had several spells cast upon it. If prepared correctly, the potion's magic restored and strengthened dead plant life, purifying growth all around the areas of the spilled concoction.
  Foxglove flowers and leaves were part of the recipe for special ink used for scribing the haste spell scrolls.