If the soil condition lends itself to the purpose, existing meadows that are poor in species of flowering plants may be converted into more diverse ones without having to revert to intensive groundwork. The presence of a habitat suitable for desired species may be obscured but may be available nevertheless. The conditions may be changed by simply adjusting mowing frequencies and schedules. How exactly it should be adjusted depends on the situation itself. When the potential and the mowing regime are in tune, one can achieve amazing results within a relatively short period of time. In this manner, many meadows situated on poor sand, loam and silt soils can, within a few years, be transformed into real flower treasuries. Hieracium species, Linaria vulgaris, Torilis japonica, Veronica chamaedrys, Tanacetum vulgare, Leucanthemum vulgare, Achillea millefolium, Campanula rotundifolia, Jasione montana and Sedum telephium are examples of species with conspicuous flowers that may spontaneously (re) appear in potentially suitable habitats in the Netherlands.
Sowing hemi-parasites of the genus Rhinanthus on grasses offers different opportunities, as practical experience with Rhinanthus angustifolius shows. Once it has established itself, its development may be quite spectacular. Its massive appearance may strongly inhibit grasses in their growth, creating opportunities for different forbs to increase or appear. Even tall vigorous grass species, such as Glyceria maxima are subdued. One can profit from this effect by introducing specific desired species in weakened, more accessible spots through sowing, for example Geranium pratense, Centaurea jacea, Dactylorhizapraetermissa, Primula vulgaris (and P. elatior).
By mowing once or twice a year at the right moments only, using additional measures as described above, one can further increase species diversity and flowering display It must, however, be made clear that sowing and planting out in really rich meadows is completely useless. The vegetation is too dense and too high to allow attractive species to develop. Seed sown in it will not germinate or the seedlings will soon perish. Planted out species suffer the same fate.