Ornament Grasses  
Hardy, elegant perennials ~ there's simply nothing like Ornamental Grasses for a stunning all season planting design. From our native prairie plant, Little Blue Stem to giant Miscanthus, no garden should be without at least a few of these majestic plants.      
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    Miscanthus in Fall
Ornamental Grasses  -  Stars of the Autumn garden.  A Brief History of their introduction to modern garden design.
There are 1,000's of different perennials in nature, but it's a relatively few number that have been adopted for use in gardens.  Ornamental grasses are mainstream now, but only a few decades ago they were a group of plants relegated to the interest of botanists, not garden designers.  
The design power of ornamental grasses is unrivaled in hardy perennial gardens.   
A garden design movement called "New Wave Naturalism", took hold in the '80's & '90's, led by Piet Oudolf in Europe and the design team Oehme & Van Sweden in America.   
This new design trend blended the unique merits of ornamental grasses with the natural forms of seedheads and mass planting, moving away from the Gertrude Jekyll style of the flowering perennial border, in vogue for most of the 20th century.   

This new design movement changed the way we design our gardens today - all revolving around the unique design power of ornamental grasses. 
                 Evelyn  
There were no commercial growers making them available to gardeners, and there was little innovation happening when it comes to hybridizing new unique colours or shapes.  For most of the 20th century, garden design was dominated by the Gertrude Jekyll-esk perennial border design style that was based on summer flower colour.   

In the 1980's there was a new wave in garden design, focused on textural plants and mass planting, for a more natural looking garden.  Inspired by the more subtle beauty of nature, it’s the non flower merits that this design movement was about – seedheads, colourful bark, the tans and golds of foliage and flower plumes, mass plantings more like what is found in nature, to create gardens that had a bold presence in all seasons.  Emphasis was much more on a plant's form and texture, rather than flower colour.  This was going on hand-in-hand with the increasing desire among gardeners for their landscapes to be less maintenance with less water needs.  

This "new wave" of garden design started in Europe with just a handful of innovative garden designers and hit north American gardens shortly after.   The name of this new garden design style was coined "New Wave Naturalism".  Ornamental grasses and sturdy, relatively common plants, were an integral part of these designs.  A trademark of this new style was how plants looked in fall and winter as being just as important as their summer flowers.  ...plants chosen and laid out in a way that didn't rely on high maintenance deadheading and other management, and that were suitable for the soil and site conditions to negate the need for supplementary water.     

The first plant breeder to recognize the garden merits of ornamental grasses and who's work inspired these desginers, was the German nurseryman and plant breeder, Karl Foerster.   Foerster developed a hybrid of Calamagrostis acutiflora that was named after him - Calamagrostis x acutiflora 'Karl Foerster'.   It has become ubiquitous in gardens all over the northern hemisphere by now, due to it's ... unique contribution to a garden's design ... it's sterile flowers that prevent the usual problem of seeding itself and becoming a nuisance ... and it's extreme hardiness and ease of growing in average garden conditions.   Foerster's inspired the New Wave Naturalism design movement with his foresight to see that we needed something truly new in our gardens.  It was only a matter of time before this new plant group was embraced by designers ready and waiting for something truly new.

When I first started collecting different ornamental grasses in the '90's, outside of this newcomer, Calamgrostis 'Karl Foerster', there were few others commercially available.   That changed quickly though as the New Wave look caught on and designers demanded better ornamental grasses availability.   The first few plants that hit the market were disasters though - many of them with runner roots that took over gardens, and other's that collapsed into a tangled mess of leaves by late summer.     On my garden consultation travels during this time, I can't tell you how often I encountered horribly ruined gardens, overrun with the aggressive roots of Lyme grass (Leymus arenarius) or Ribbon grass (Phalaris arundinacea) for example.  These early entries to the marketplace charmed everyone with their bold diagram of runner roots.coloured leaves while still in pots at the garden centers in spring, but in the garden they were a disaster and many people turned away from trying any of the other really wonderful new grasses coming to market quickly.   (C. 'Karl foerster' looked so boring in a pot by comparison, that most passed it over!).    Grasses were so new to gardeners, the assumption was that all of them behaved in a similarly unruly fashion.    It took a while for gardeners to be convinced that other grasses were safe to use ... and the  rest is history.    Today, there are dozens of new cultivars of each of the main ornamental grass species available and you'd be hard pressed to find a garden designer that doesn't integrate them into their planting design. 

Innovators of the New Wave Naturalism Garden Design Movement in the late 20th century.
Ornamental grasses are pretty much the only major group of plants that are relatively new to the horticulture industry.   The New Wave Naturalism style was launched in the 80’s by the famous American design team of Wolfgang Karl FoersterOehme & James van Sweden in the US and the Dutch designer Piet Oudolf in Europe,  working together with plant breeders the likes of Karl Foerster. 

Karl Foerster.  This German nurseryman's foresight was the original inspiration for this new design movement, with the introduction of an important new hybrid of two species of Calamagrostis acutiflora native to Europe and Asia.  He apparently discovered the species in the 1930s along a railway in Germany and the story goes that he pulled the emergency brake on the train he was riding in order to collect the plant he saw out the window. The resulting cultivar ‘Karl Foerster’ was named to honor him.   (link to more about him).

Piet Oudolf.  Piet Oudolf Using large sweeps of contrasting texture and subtle colours, using grasses and texturally interesting flowers and seedheads, Oudolf’s designs celebrate fall and winter interest as at least 50% of a garden's potential beauty.  Winter gardens full of dreamy billows and frost kissed flower stalks and seedheads are his trademark.

Wolfgand Oehme & James Van Sweden took this concept further in the direction of even larger mass plantings based on a small plant pallet to create dramatic landscapes.   Their own take Oehme & Van Sweden designerson this new wave of garden design was inspired by the North American prairie lands and was called "The New American Garden Style".  In their book Gardening With Nature, they pay homage to the plant breeder Karl Foerster who's inspiration this new style was built on.  

Another innovator, Adrien Bloom of the world famous Blooms of Bressingham nurseries Adrien Bloomin the UK, uses grasses in a more traditional way, within richly mixed perennial and shrub gardens, which is the way most of us want to use grasses - combining the best of the previous Jekel-esk style and integrating some of the plants and textural features of the New Wave style.    His gardens as a rule use single specimen grasses as opposed to the “New Wave” innovators who launched the trend of sweeps of mass plantings.


Try some of these wonderful plants!  We see the giants out there, like the Miscanthus sinensis cultivars, but there are many only just 2 - 3 feet tall that would fit nicely among your flowering perennials in even the smallest garden. 

                  Cheers! Evelyn  
 
©Evelyn Wolf, 2019.  All rights reserved.  Contact for permission to use.
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 Poacea family—true grasses.  Two distinct groups that matter to know the difference on - warm season growers & cool season growers.  

Gardener’s tend to group all grasses together as though they are all in the same genus, but just like our standard perennials, each plant genus and species group has it’s own unique needs, bloom times, and soil / water needs.      

Something to take note of when deciding how to use a particular ornamental grass in a planting design is whether it is a WARM SEASON grass that doesn’t bloom until late summer / fall, or a COOL SEASON grass that rushes to growth in spring.     Many warm season grasses are so late coming out of the ground in spring, many gardeners think they’re dead!    At the garden center as well, when your main shopping trips in spring present you with scrawny looking wisps in a large pot with a large price tag — the warm season grasses are just not much to look at that early in the season!   It’s the fall and winter look of true grasses that makes them so important to include in a garden's design.
 
So, warm season grasses are a great choice for planting together with spring tulips and early summer bloomers.  ...and because they're so large, I like to use them to the south of a few sensitive plants to shade them from the hot mid-summer sun.   Comfortable in the shade of the tall grasses, spring blooming primulas or pulmonaria finish the season without damage and bloom again in the full sun left by the dormant grass next spring.

 General Maintenance of Ornamental Grasses.
Water.  Most of the true grasses will give the best show if they have, above all else, exceptional drainage, and NOT growing in overly fertile soil.   Overwatering warm season ones in particular often leads to outright death from crown rot.   There are gold Hackonachloaexceptions to this though—Imperata, Hachonechloa, Carex mainly.  These are among the few ornamental grasses hardy to our zone that are moisture lovers, native to wetlands.    Most of the others—Miscanthus, Calamagrostis, Pennisetum—are native to the open prairies of the world and are tough drought tolerant plants.  

If the tag says drought “tolerant”, they are probably drought lovers! and need to have their crowns above damp soil at all times.  The moisture lovers, like Imperata and Hakonechloa, as a rule, grow from underground runners, and moisture at the crown poses no threat.  Good drainage is still important though, just as with most perennials.

Maintenance - Leave them stand over winter and, for the warm season types, cut all the old foliage stems down to 2” in early April before new growth begins.   On the evergreen types like Fescue or Deschampsia, a gentle combing with a rake or spread fingers will loosen the dead leaves and leave the live ones clean and ready to perform for a new season.  STAY AWAY from the root runner types like Phalaris (ribbon grass) or Leymus (blue lyme grass) - they’re just not worth the trouble and don’t have any of the elegance of the clump forming grasses.  Watch plant tags for “clumper”.

Fertilizing.   Don’t! ...it only leads to weak lush leaf growth that flops open. 
  
 Dividing.      Dividing ornamental grasses is more or less the same as dividing any perennial, just much  harder.  Getting an established clump of Calamagrostis or Miscanthus out of the ground is a job for machinery!  With the larger Miscanthus in particular, if you don’t have a Bobcat at your disposal, cut into the ground with a large sharp knife or saw and dig out clumps in pie shaped sections, one at a time, with a strong shovel, sturdy enough to not bend as you lever the roots out of the ground.   

If you can get the whole clump out of the ground the idea of “prying gently apart with a garden fork” is a joke—something more like an axe is required.  Soaking the root ball in a bucket of water is essential since you’ll be awhile before you can get your divisions safely back in a pot or the ground. 

Discard the old, choked, and often dead center of old clumps and concentrate on getting sections from the outer ring—that’s the most vigorous part of the plant. 

  

My favourite Ornamental Grasses.     I've experimented with just about all the different ornamental grasses over the years and I've yet to find one that doesn't contribute something unique to my garden's design.  Here's a profile of most of the ornamental grasses I'd recommend, that are fully hardy for our zone 4, York Region climate.  (BRAND NEW PAGE AND I'LL GET THIS LIST UP SHORTLY!)    Cheers! Evelyn
 



 


  Remember to look for the botanical names on plant tags when purchasing.  Many of the common names are vague or so similar to others, that it’s hard to be sure you’re getting the plant you want.  When they’re young and in a pot, it isn’t easy to distinguish differences.   It's also not easy to easily see the merits of a potted ornamental grasses.  Do some homework first to determine the ones you want, then go out by them based on the exact name ma