How to Prune blunt greenhood?
No pruning required, remove spent flower spikes as necessary

blunt greenhood · Pterostylis curta
Grow in terrestrial orchid compost in full light, with shade from hot sun and night temperatures between 8 and 10°C; water sparingly only once the growth point emerges, increase watering as leaves develop and use orchid fertiliser when in full growth. Reduce watering when leaves start to yellow and dormancy starts, dormancy lasts 2-3 months when temperatures should be kept at 20-25°C with occasional misting only. Repot during the dormant period.
No pruning required, remove spent flower spikes as necessary