The author’s experience suggests that, as a result of diminished competition, herbaceous plants are more readily established by planting in these types of vegetation, for example,
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6.18
Creating prairie vegetation at the Eden Project by, first, planting then immediately afterwards sowing a prairie mix over the top: (a) the site immediately after the completion of planting and sowing in March; and
(b) the same site two growing seasons later in August
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6.19
The same principle applied to a garden. May to June flowering herbaceous plants, such as Iris sibirica and Thalictrum aquilegifolium flower above a sown sward of late summer flowering prairie plants. By July, the former will have finished flowering and will be hidden by the 1 m plus prairie plants
randomly at the specified intervals. The timing of establishment is typically determined by the needs of the sowing, as with container-grown stock, the planting date is much more flexible. Over-sowing previously planted stock is well suited to situations where relatively weed-free subsoil, sand mulching or abundant skilled labour is available. The author has used this technique to successfully establish prairie vegetation on a number of sites, including the Eden Project in Cornwall (Figures 6.18 and 6.19).
