I remember being told that if you put tulips together in a vase with other flowers, the other flowers would die because of something in the tulips. And that, similarly, tulips poison the soil they grow in. is this true?
Yes tulips can poison your soil.
Once the tulip has flowered the petals should be removed and the foliage should be allowed to discolour before being removed. Do not let the foliage die back into the soil as this is when it can poison the soil, it's called "tulip fire".
As for mixing tulips with other flowers in a vase, I don't think there are any problems with tulips, but daffodils release a chemical that shortens the vase life of other cut flowers. You can still mix daffodils with other flowers but you have to soak them first to release the chemical.
Answered by Green Shoots Landscaping from United Kingdom, Crieff, in June 2010.
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