You may have heard gardeners talk about companion planting. This practice is based on the belief by many gardeners that certain plant groupings are in some way beneficial.
There is much argument as to whether some aspects of this belief has any scientific basis. An investigation into whether certain plant combinations work or not could form an interesting investigation for children to undertake; for instance do nasturtiums attract aphids away from broad beans or do marigolds repel whitefly away from tomatoes.
There is little doubt, however that flowers do attract beneficial insects which can only be a good thing. They provide another dimension to a vegetable patch. Not only by providing colour and the opportunity to study insects at close quarters but also by providing a crop of cut flowers for the classroom.
If you have space a patch of native wild flowers is especially effective in supporting a range of indigenous insects. A patch of nettles tucked away in a corner will provide a food plant for many butterfly caterpillars (don't worry not cabbage whites!) and the leaves (not roots) can be used on the compost heap. Also a patch of grass that is allowed to form seed heads attracts many insects. To provide a food supply for as many insects as possible you need to choose different shapes of flowers e.g. tube shapes and daisy shapes.and also have some flowers that grow throughout the season.
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