Over the course of this school year we have been discussing WANTS and NEEDS in relation to ourselves. We discussed that while you may WANT something that there are actually a few basic NEEDS that are necessary for survival. For human beings these are: air, water, food, shelter (including clothing), and we added in ‘love’ (families).
Students have also been learning about what a plant NEEDS to survive. In this experiment we wondered if all plants need soil in which to grow. We took a sea sponge and put it into a plastic container. We soaked it with water, and ensured that there was always water in the bowl to keep it wet. Grass seeds were sprinkled over the sponge. You can see the result …
So while we usually think of plants needing soil – and a great many of them do need soil – clearly not ALL plants do. We also tried this experiment with grass seeds on a pine cone. While some grass grew in the bottom of that container (in the water) none grew on the actual pine cone. Perhaps it wasn’t kept wet enough …