There's a link to caterpillar host species here, Deschampsia cespitosa (no reason to think cultivars like 'Goldtau' wouldn't be acceptable), Garlic Mustard (I call it Jack-by-the-Hedge), and Honesty have potential for your site. Oh and nettles, of course. https://www.wildlifetrusts.org/actions/how-attract-butterflies-your-garden
"What is hateful to you, do not do to your neighbour".
Thank you all again, I think I have plenty of suggestions now. Just to go through, work out positioning in the bed and do the actual hard work of clearing it ready for planting!
Can I put another vote in for Lamium? I have one in my shaded corner and it has flowered since March and is covered in bees during the day and moths on an evening. It's Purple Dragon (Lamium maculatum). My collection of heucheras are also always covered in bees and hover flies and love shade.
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