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Molinia caerulea subsp. caerulea  'Overdam'

Molinia caerulea subsp. caerulea 'Overdam'

This is an amazing little grass, beautifully proportioned and very well behaved. It grows and flowers and doesn’t get more than 45cm tall, (unlike its larger cousins) and is therefore perfectly suited to the front of a bed or border. Here at Harlow Carr it edges up the front of our main borders.

As the weather turns colder the grass and inflorescences get more and more bronzed, until it almost glows golden. This is especially effective in the short winter days - when the sun sets it seems to light up this particular corner of the garden.

It needs very little attention; we cut it back hard in February/March each year and it will cope with any well drained soil, in full or partial shade. 

Vital statistics

Common name
Purple moor grass 'Overdam'
Family
Poaceae
Height & spread
Up to 0.5m (20in) tall and wide
Form
Clump-forming deciduous grass
Soil
Moderately fertile moist but well-drained, preferably acid.
Aspect
Full sun or partial shade
Hardiness
Fully hardy

Molinia

This is a genus of two perennial species of elegant late-flowering grasses with tall, arching sprays of flowers. They grow on wet heaths and moorlands throughout western Europe to Russia, and eastern Japan, although can tolerate drier conditions.

The only species generally grown in cultivation is a clump-forming grass with green, pointed, deciduous leaves. Purple-green flowers with purple stamens open in late summer, and the foliage provides a splash of autumn colour. It's a good plant for catching the wind, and in general is a very versatile garden plant.

Molinia caerulea subsp. caerulea  'Overdam'

Molinia caerulea has been divided into two subspecies (subsp. caerulea and subsp. arundinacea), although recent research now points to the differences in the plants being down to soil conditions rather than genetics.

The species can grow a metre or more tall, and some cultivars even taller. Molinia caerulea subsp. caerulea 'Overdam' is smaller than most, usually no more than 50cm tall, making it suitable for the front of a border. 

Cultivation

  • Cut back in late winter or early spring to remove dead foliage and flower stems. New growth will appear from the base.
  • Generally free from pests and disease.

Propagation

  • Propagate by seed (though offspring may not come true to the parent) in pots in a cold frame in spring.
  • Divide in spring.
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