Toxicity of Purple Hyacinth Bean Plant Uncooked seeds are poisonous, with toxic levels of cyanogenic glucosides. They can cause vomiting, breathing problems and convulsions.Click to see full answer. Beside this, is purple hyacinth bean invasive?The hyacinth bean is not invasive.One may also ask, are hyacinth beans poisonous to dogs? The toxic principle of these plants is very concentrated in the bulbs (versus the leaf or flower), and when ingested in large amounts, can result in severe clinical signs. Severe poisoning from hyacinth or tulip poisoning is often seen when dogs dig up freshly planted bulbs or having access to a large bag of them. Keeping this in consideration, can you eat hyacinth? Not Every Flower is Edible Before eating any flower, you need to make sure it is edible. Some flowers, however, even organic ones, can make you very sick if eaten. Daphne, foxglove, daffodils, and hyacinths are just a few examples of poisonous flowers that should not be used for food purposes.What does a hyacinth bean look like?A vigorous ornamental annual vine, purple hyacinth bean plant (Dolichos lablab or Lablab purpurea), displays beautiful pinkish-purple blossoms and interesting reddish-purple pods that grow to be about the same size as lima bean pods. Because of this, the hyacinth bean is also known as Jefferson bean.