How to Prune creeping blue blossom?
Usually little pruning is needed. Lightly shape if necessary, removing dead, damaged or diseased shoots. Prune after flowering has finished.

creeping blue blossom · Ceanothus thyrsiflorus var. repens
Grow in fertile, well-drained soil in full sun with shelter from strong, cold winds. Lime tolerant but may become chlorotic on shallow chalk soils. See ceanothus cultivation
Usually little pruning is needed. Lightly shape if necessary, removing dead, damaged or diseased shoots. Prune after flowering has finished.