No hardscape. No focal stone. Just plants, planted in ranks, and a discipline about trimming that most people abandon by week four.
A Dutch tank is planted in bands running front to back, each one a different species and height. The gaps between them are the whole point.
Staurogyne repens, Lobelia cardinalis ‘mini’
5–8 cmCryptocoryne wendtii ‘brown’, Alternanthera reineckii ‘mini’
10–15 cmRotala rotundifolia, Ludwigia palustris
20–30 cmLimnophila aromatica, Pogostemon erectus
30–40 cmVallisneria nana, Rotala macrandra
40 cm+
They are under-planted at setup. A Dutch scape wants to be seventy per cent covered on day one, which feels absurd and expensive and is nonetheless correct.
The second reason is the trim. Stems are topped and replanted, not cut back — and if you skip a fortnight the streets merge and never separate again.