Miscanthus sinensis 'Morning Light'
A fabulous architectural grass with white edged leaves and purplish seed heads.  One of the taller grasses at around 1.2m high, it looks amazing as a specimen in a mixed herbaceous border. 
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Hakonechloa macra 'Alboaurea' - NEED LINK
A really beautiful mound forming grass with green and yellow leaves that blend to give a golden appearance.  Makes a lovely ground cover and will tolerate shade.  Looks great planted around the base of a tree.
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Deschampsia cespitosa
Another mound forming grass, I grow this one for its airy, fluffy, silver flower heads.  It makes a great addition to a herbaceous border.  I like to use it for punctuation amongst perennials where it helps to blend the different plants together.   It can be planted at the front of the border and when it flowers you can see the plants behind it through the gauzy curtain of its flower heads.
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Eragrostis elliottii
A mound of fine blue leaves and a head of airy flower spikes makes this one of the most beautiful ornamental grasses. It grows up to 1.2m tall and makes a great addition to a mixed herbaceous border. 
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Pennisetum villosum
This is one of my favourite grasses. I always try and plant one whenever I design a garden.  It has a small mound of slender dark green leaves and really lovely flowering heads that end in tiny soft bottlebrushes.  It is commonly  known as Fountain grass as it's flower heads tumble over to create the effect of a water fountain. 
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Carex aurea
A really useful grass that will grow in the shade.  It forms a mound and has attractive little brown, feathery flower spikes in the Spring. I love to plant it next to some really dark leaved Heuchera, or the purple leaved Bergenia.
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