How to Prune blue heath?
Shorten flowered shoots to about 1.5–2.5 cm from the previous year's growth. If flowering is on last year's growth, prune after flowering; if on current-year growth, prune the following early to mid-spring.

blue heath · Phyllodoce caerulea
Grow in moderately fertile, humus-rich, moist but well-drained acid soil. Does best where summers are not too hot
Shorten flowered shoots to about 1.5–2.5 cm from the previous year's growth. If flowering is on last year's growth, prune after flowering; if on current-year growth, prune the following early to mid-spring.