Compact plant for rose border edge

[Curver]

I’m going to plant a rose border to house some of my David Austin collection. I was considering planting a hedge like edge with lavender but I’m worried it’ll look a mess.
Is there a compact plant that would do well? I could still do lavender if anyone has any tips to make it not get unruly! Full sun patch. Thank you.

How about an edging of Dianthus plants? Generally small compact plants that like sun, and often beautifully scented.

Examples: https://hayloft.co.uk/delightful-dianthus-collection-g-k39282

DA has recommendations here https://www.davidaustinroses.co.uk/blogs/inspiration/companion-planting?srsltid=AfmBOooyQizco7mH94nbwDV_7-ghuV4SJvnLvDwST2vGDJvRn9DvxQDb

I think lavender sounds lovely but in practice it could look quite scruffy. Maybe embrace the scruffiness and go for a hardy geranium? That's a lot less work. Sarah Raven recommends salvias because they give off compounds that act as a fungicide. Or you could also think about something really compact like thyme or other herbs.

Is there a compact plant that would do well?
A dwarf box hedge?

People are giving up on box because of blight and box moth caterpillar. Ilex crenata is an alternative though.

OP - how about thyme, or prostrate rosemary?

Hadn’t thought about using herbs! That could look lovely. Thank you.

Salvias go well with roses, there's quite a range of colours and sizes.

Nepeta - one of the smaller cultivars. Can get three flowerings if you cut back after the flowers fade.