Ornamental Grasses

A new and completely different look can be introduced to your garden with ornamental grasses. The upright slender arching forms are interestingly different from the shape of most shrubs and other perennials.

The colour ranges through mauve-amethyst shades of blue, to gold and tan. Variegated leaves of green and white or green and gold add distinctive colour throughout summer and a few have added winter interest, maintaining dried foliage and plumes of flower heads even amidst snow and ice.

This “Green Thumb Guide” will present to you just an overview of the main ‘genera’ we have to offer at Humber, with some main cultivars.  For all varieties and descriptions please view our price list PL914.

Ornamental grasses that seemed so new and
revolutionary just a few years ago are now regarded as old friends.  Their variety and ease of culture have made them essential landscape plants and there is an ornamental grass suitable for almost any garden situation.
 

HARDINESS OF GRASSES:

VERY HARDY:  Grasses that have been tested over many years at both Agriculture Canada Research Station in Morden, Manitoba and at the Minnesota Landscape Arboretum in Chanhassen, Minnesota.

HARDY, VERY HARDY
100% TWO YEAR GUARANTEE

TENDER = NO GUARANTEE OVER WINTER.
Must be used as an annual or lifted from the garden and stored indoors for winter. If you have a sunroom or space in a sunny window they can be kept growing or they can be cut back and kept in a cool room.

CULTURE AND MAINTENANCE:

Annual grasses are grown from seed each year.  For earlier flowering, the plants can be started indoors, or the seed can be grown directly in the garden after the danger of frost is past.  Spacing for most plants is 6 to 12 inches apart.  Almost all annuals prefer full sun and require only adequate moisture and fertile soil for good growth.

Perennial grasses can be grown from seed, but are usually purchased as plants.  Spacing for plants approximately 4 feet tall is 2 to 3 feet apart; larger plants require more spacing whereas shorter plants can be spaced about 1 foot apart.  Most perennials prefer full sun or, in some cases, partial shade.  Many of the perennial grasses are showiest in late fall.  For this reason, it is desirable to carry out the cultural practices of division and cutting the plants back to the ground in early spring.  The practice of cutting the plants back within 6 inches from the ground is especially desirable for large, dense plants.  Removing the previous year’s growth has the following advantages: (1) ensures vigorous growth, (2) acts as a pruning method for removal of dead stems, and (3) creates a more-attractive plant.  Division of perennials should occur about every 7 to 10 years.  Some species can grow in place for several years and actually look best when allowed to do so.  All divisions should be made when the plants are dormant or just before they begin to grow in early spring.  The need for division is determined by the appearance of the new growth in the spring.  If a plant shows signs of growth only around the edges and not in the center, the middle of the plant is probably dead and the plant should be divided.  Grasses that show uniform new growth can be left in place for a longer period of time.

The only cultural practice that may be necessary is staking the flowering stems of some of the larger plants.  If the plants are grown in shady locations with very fertile soil, staking may be necessary.

Areas of interest, and uses for your Ornamental Grasses.

FEATHER REED GRASS
Calamagrostis acutiflora ‘Karl Foerster’ and ‘Strictus’ (125 cm)
Suitable for small gardens.  Pinkish flower heads in late June turning to tan.  The narrow dried flowers mass effectively giving special interest all summer.  Sun.  The variety ‘Overdam’ is smaller with grey leaves striped white or pink.

FALL REED GRASS
Calamagrostis var. brachytricha (120-150 cm). 
Beautiful glistening flower heads in September-October.  An upright neat grass.  Full Sun.

TUFTED HAIR GRASS
Deschampsia
The various cultivars of Deschampsia may at first seem rather similar but each has its own special colour difference at flowering time.  This can be best appreciated when two or three types are grouped together in the garden.  They prefer moist soil in sun or partial shade and are good plants for areas getting only part-day sun.
‘Bronzeschleier’, ‘Goldgehaenge’, ‘Schottland’, and ‘Tautreger’ (60 cm)
Mound forming evergreen perennial grass.  Leaves are dark green.  Inflorescence appears in late summer, an open feathery panicle to 50 cm long and 20 cm wide.  Dries well for winter arrangements.

EULALIE
Miscanthus
In Humber Nurseries’ remarkable collection of ornamental grasses our large selection of Miscanthus varieties is particularly notable.  Upright clump-forming plants, all with showy plumes that are a delight in the summer and fall garden.  They have all proved to be very hardy and can stand up even under snow and ice, adding interest to the winter scene.  Annual maintenance requirements are cutting them back in spring.  They are disease & pest free and tolerant of many soil conditions, but best in moist soil in full sun.  In the descriptive listing that follows, you will find a number of dwarf varieties suitable to smaller gardens and then a range of heights up to the Miscanthus floridulus that is the tallest.  The colours of the showy flowerheads can vary from whitish-silver to gold and to a chocolate-red, all eventually drying to a fluffy tan.

Miscanthus sinesis variegatus has green and white striped foliage.  Porcupine Grass and Zebra Grass are cross banded with yellow stripes.

SEDGE
Carex
Differing botanically from true grasses, sedges provide us with wide choice of foliage colour and texture.  Particularly
valuable for growing in shade or in moist areas and mostly evergreen.  Enjoys moist soil in sun or shade.

SWITCH GRASS
Panicum virgatum (1 – 2 m)
Clump-forming upright plants with diffuse, fine-textured panicles of flowers.  The variety ‘rubrum’ shows red in the foliage in mid-summer and other cultivars become a rich red in the fall.  The foliage turns yellow in winter but they can be left standing to good effect.  They are tolerant of almost any soil, from dry, sandy soil to heavy clay or wet soil.  Most effective in large sweeps or groupings.  The height can vary considerably depending on how moist the soil is – only about 1 m in dry soil and 2 m when moist.  An excellent variety at only one metre is ‘RUBRUM’ that colours to red as early as July.  Some named varieties are ‘Rostralbusch’, ‘Warrior’, ‘Squaw’ and ‘Heavy Metal’.

FOUNTAIN GRASS
Pennisetum
These mostly mid-sized clump-forming grasses are valued for their showy foxtail-like plumes effective singly or in groups.  They vary greatly in their hardiness, from very hardy to very tender.  Perhaps the most handsome is Purple Fountain Grass with striking red foliage and large red flower plumes.  Unfortunately this is a very tender variety and cannot even take frost.  It needs to be lifted and potted-up before the first frost and can be wintered as a house plant in a sunny location.  Do not cut back severely but leave at least
15 cm of stem.

HARDY FOUNTAIN GRASS
Pennisetum alopecuroides  and the cultivars ‘Cassian’, ‘Hamelin’, and ‘Moudry’.

TENDER FOUNTAIN GRASS
Pennisetum setaceum rubrum and ‘Burgundy Giant’, P. ruepelli and P. villosum. These tender varieties must be lifted in the fall and wintered indoors.

BLUE FESCUE
Festuca cinerea ‘Elijah Blue’ (15 to 30 cm)
A very popular metallic blue grass.  Good in borders or rock gardens.  Evergreen clumps of blue-silver foliage.  Also ‘Blaufuch’s’ and ‘Sea Urchin’.  Sun, partial shade.

LILY TURF
Liriope – for fall flowers (30 cm). 
Many texts that give hardiness ratings suggests the Lily Turfs are not hardy enough for our area.  We can only say that we have grown them successfully over many years at our location in Brampton and have suffered no losses even over the severe winter of 1993-94. Their August-October flowers in shades of lavender, purple and pure white make them particularly valuable.  They can be grown in sun or shade.  Even in deep shade the flowering is not diminished.  The foliage is totally evergreen which can contribute much to the winter landscape.  The old leaves should be removed in spring before new growth appears.

PURPLE MOOR GRASS

Variegated Molinia forms a neat arching clump of green and gold striped leaves and golden flower stems.  Small upright varieties to combine with perennials are – ‘Heidebraut’, ‘Moorhexe’, and ‘Strahlenquelle’.

The tall Purple Moor Grasses have a see-through look as all the leaves are in a basal clump.  ‘Altissima’, ‘Karl Foerster’, ‘Skyracer’ and ‘Windspiel’. The smaller Molinia remain standing in winter, the taller variants do not.

MONDO GRASS
Ophiopogon
Grass-like member of the lily family.  Partial shade to shade in moist soil.  The Dwarf Mondo, Silver Mondo and Black Mondo can take full sun if in moist soil.