The Trail is a proper stony green-grey, and the trick with it is restraint. It wants quiet, considered company — not a brilliant white slapped next to it, which will read as cold and clinical against that muted register.
Start with the whites. Reach for cool warm-whites rather than anything stark. You want a ceiling and trim that sits softly beside The Trail without bleaching it out. A whisper of warmth keeps the whole scheme grounded and stops the green-grey from tipping grey and flat.
For a tonal lift in the same family, Dulux Almost Pistachio (LRV 80.3) is a lovely move — light, soft, faintly green, and bright enough to lift a darker scheme without breaking the stony mood. Use it on adjacent walls or a hallway running off the main room.
When you want contrast with backbone, go deep rather than bright. Paint & Paper Library Blue Blood (LRV 16.4) brings a rich, inky depth that anchors The Trail beautifully — cracking on a chimney breast, a study or joinery. Or Mylands Cigar BH.20 (LRV 11.8), a warm dark brown that adds earthiness and stops the palette feeling too cool. Both pull their weight without shouting.
Let the materials do the rest. Linen, slate, pale unfinished wood — these are The Trail's natural partners. The green-grey speaks through them rather than over them.
On metals: cool only. Nickel or blackened steel keep the stony register intact. Brass and warm bronze will fight it and look slightly off, so save those for a warmer room.
Practical advice: sample The Trail on at least two walls and live with it through a day — green-greys shift hard between morning and evening light, and a north-facing room will pull it cooler. Paint your white sample right beside it so you can judge the relationship, not the colours in isolation.