UK pruning guide · RHS timing
When to prune pony tails grass in the UK
Why the timing differs here
For shrubs that flower on the current season's growth, the RHS times pruning to early or mid spring — after severe weather has passed and once the growth buds begin to swell. In Britain that is usually March into April rather than the February common in warmer regions; prune too early and the new shoots meet a late frost.
How to prune pony tails grass
Wear gloves and run fingers through the clump to pull out loose dead blades, then shear the whole clump back by one-third to one-half with scissors or shears. Avoid cutting into the crown at ground level.
Pony Tails Grass (Stipa tenuissima, also sold as Nassella tenuissima) is a deciduous to semi-evergreen fine-textured grass. Comb or rake out dead tawny foliage in late winter and cut the clump back by roughly one-third to one-half before new growth starts. This refreshes the plant and prevents the centre from dying out.
More pony tails grass care for British gardens
Care at a glance
Pruning pony tails grass in the UK — FAQ
When should I prune pony tails grass in the UK?
Prune pony tails grass in early to mid spring. For shrubs that flower on the current season's growth, the RHS times pruning to early or mid spring — after severe weather has passed and once the growth buds begin to swell. In Britain that is usually March into April rather than the February common in warmer regions; prune too early and the new shoots meet a late frost.
Is it illegal to prune pony tails grass in spring or summer in the UK?
There is no nesting-bird restriction that realistically applies to pony tails grass, since birds do not nest in it. The Wildlife and Countryside Act 1981 still protects any active nest you do find anywhere in the garden — the rule is about the nest, not the plant.
How do you prune pony tails grass?
Wear gloves and run fingers through the clump to pull out loose dead blades, then shear the whole clump back by one-third to one-half with scissors or shears. Avoid cutting into the crown at ground level.
How often does pony tails grass need pruning in a British garden?
Annually. Pony Tails Grass (Stipa tenuissima, also sold as Nassella tenuissima) is a deciduous to semi-evergreen fine-textured grass. Comb or rake out dead tawny foliage in late winter and cut the clump back by roughly one-third to one-half before new growth starts. This refreshes the plant and prevents the centre from dying out.
Why is UK pruning timing different from American advice?
Most pruning guides online are written for US conditions and anchored to USDA zones. Britain's maritime climate gives milder winters but later, less predictable last frosts — from March in the south-west to mid-May in the north — so the RHS advises against winter pruning for most plants: it pushes out soft growth that a late frost then kills. Britain also has the nesting-bird law, which has no US equivalent.