As I know, the leaf of the tulip is poisonous. Is it safe to grow vegetables with tulips in the same bed.
Thank you for your great question to Toronto Master Gardeners.
As to the poisonous nature of tulip bulbs, there is a clear answer on the Government of Canada website, on its Canadian Biodiversity page.
“General poisoning notes:
Tulip (Tulipa spp.), including Tulipa gesneriana, is a widely cultivated plant used as a perennial spring flower in Canada. Many species and hybrids as well as numerous cultivars of tulips may be found in Canada. Tulips contain an allergen, tuliposide A, which causes dermatitis in sensitive individuals. Poisoning of humans and dogs has also been reported when tulip bulbs mistaken for onions were ingested. The allergen tuliposide A is also found in the Peruvian lily (Alstroemeria spp.), and there is cross-sensitivity to onion and garlic (Allium spp). Tulips are not normally a problem to humans, but sensitive individuals should avoid touching the plants (Mitchell and Rook 1979, Cooper and Johnson 1984).”
The Michigan Cooperative Extension also advises that the bulb is poisonous if ingested by humans and small mammals. However, the bulb does not emit any known toxins. There is no danger of poison spreading underground to other vegetables. The one caution with vegetables: do not plant onions or garlic near bulbs. This will avoid confusion at harvest time, as they all look so similar.
More information on the symptoms of the poison is available at The Nova Scotia Museum website. Search Plant Poisons, then Tulips.