Figure 1
As a follow-up to our tomato-growing, we set out to investigate the effect of growing cress in different media. We are trying to do this as a “fair test”, though already problems can be seen. We set up containers with compost, a sheet of paper towel sitting on a plastic tray, sand, and soil from our garden (see Fig 1).
When growing cress on paper towel previously we had a problem with the paper drying out around the edges, so the seeds were sown in the centre of the sheet. This was done by cutting a circle from the centre of a sheet of card, which was placed in turn over each medium, and then sprinkling the seeds on the exposed paper towel, soil, compost and sand. This also helped to overcome concerns about the different shapes of the containers of the media and inconsistencies in sowing patterns and seed density. This last concern still exists, however, as we relied on judgement to allocate equal quantities of seeds to the 4 media.
Finally we covered each container with a sheet of cardboard to encourage germination. Our principal observations will be the time of first germination and the height of the cress. Taste may also play a part.
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SCIENCE Experiment of the Week |
Growing Cress 21 June 2008 |