Asphodeline lutea (Asphodel): Vertical spikes of sulphur yellow flowers in early to mid-summer. Hardy, but dislikes heavy soil in winter. To 1.2m

Hemerocallis citrina (Long yellow day lily): Fragrant lemon, yellow lily flowers on long stems above green strappy foliage. Flowers open in evening. Hardy. Up to 1.2m.

Hemerocallis lilioasphodelus (yellow daylily): Fragrant lemon yellow lily flowers above green strappy foliage. Semi-evergreen. Flowers typically open in the evening. Hardy. Up to 1m.