Getting Water Hyacinths to Bloom in a Cool Climate

The beautiful water hyacinth, Eichhornia crassipes, a floating plant popular in water gardens, is known for its spikes of violet flowers reminiscent of hyacinths by their shape (but not their scent). It has curious swollen air-filled leaf petioles that help it float (they look like they had swallowed a tennis ball!) However, a water hyacinth will often bloom little or not at all in temperate climates. The problem? It needs heat in order to bloom and it finds the temperature in many temperate water gardens positively frigid. Instead of launching your water hyacinth into a big pond that will take ages to heat up, try growing in a pot of its own in a very sunny location protected from the wind (thus warmer than normal). And choose a black or dark pot that absorbs heat. Try that and you will have flowers all summer long!