Latin Name

Schoenoplectus tabernaemontani 'Albescens'.  (Synonym:

Schoenoplectus lacutris ssp. tabernaemontani 'Albescens',

Scirpus tabernaemontani 'Albescens' .)

Common Name

White rush

Family

Cyperaceae, the Bulrush family.

What kind of plant is it?

Hardy aquatic reed.

Hardiness

Zones 5 - 8.

Habit

Colony-forming, with stems arising from the ground with shocking verticality. 

Rate of Growth

Fast.

Size in ten years

A colony four to five feet tall above the surface of the water.  Schoenoplectus should be grown only in containers that are no more than half as wide as it is tall, sited in the middle of large ponds.  The stunning display of the stems' erupting verticality would be lost if the colony were grown in open ground shore-side, where most of the stems would be snapped anyway; they are unusually fragile if touched, let alone handled.  Even the largest container will be filled with growth in three years. 

Texture

Uniquely open and delicate, and yet thrustingly energetic.

Grown for

its habit: The leafless stems are much narrower than those of most other aquatic verticals, such as cat-tails, Typha latifolia; or papyrus, Cyperus papyrus; they are narrower even than those of scouring rushes, Equisetum hyemale.  (As with papyrus, the leaves themselves are reduced to sheaths at the base of the stems.)  Unlike Typha or Cyperus, the inflorescence at the tips of the stems of Scirpus is minute, providing almost no interruption to the stems' clean-lined soaring.

its coloring:  The stems of 'Albescens' are creamy white, with only modest vertical stretches of green.  From any distance, the look is an unvariegated pure white.     

Flowering season

Spring: late Spring here in Rhode Island: May into June.

Color combinations

The unusually prominent—and prevalent—white of Schoenoplectus goes with almost anything. 

Plant partners

Schoenoplectus benefits from the same considerations in plant partners as papyrus.  Take advantage of the opportunity to contrast with the rush's unusual height and strict verticality.  The larger the leaves, shorter the height, and broader the habit of partner plants, the better.  The round floating leaves of water lilies, then, could only be surpassed by the even larger round leaves of lotus.

If you have the ultimate in water gardening budget and pond size, the giant Amazonian lily, Victoria amazonica, is the plant for you.  Its round leaves can be five feet across.  Astoundingly, its best performance is when grown as an annual.  My reflecting pond is ony eight feet wide, but it's seventy feet long.  Victoria is on my bucket list.  'Longwood White' is a more practical cultivar—if any aquatic annual with a potential width of ten to forty feet could ever be described as practical—because it's more tolerant of temperatures that aren't as oppressive and sweltering as those in an equatorial jungle.  Handily, its leaves also have a showy red rim that would contrast sharply with bright stems ofSchoenoplectus.

On a much smaller scale, calla lilies are a terrific partner, with large pointed leaves and dense but comparatively low growth.  They also thrive in sun or shade, so can be grown right alongside a Schoenoplectus colony.  Both calla lilies and water lilies have cultivars with deep-hued flowers that would contrast well with the bright Schoenoplectus stems.

Elephant ears in the Colocasia genus grow well in shallow water, and there are cultivars that also celebrate dark and woody colors.  In particular, 'Diamond Head' has leaves of shiny ebony.  What a thrill to have a container of Schoenoplectus backed by a billowing black colony of it.

I'm hoping to establish nearby colonies of the largest-leaved hardy aquatic, Lysichiton americanus, the Western skunk cabbage, whose banana-shaped leaves can be three feet long.  My water-garden plans also includes thriving colonies of hardy mangrove, Leitneria floridana; young plants were installed just this Spring.  Its shiny green leaves are nearly as big as those of peach trees.     

Where to use it in your garden

Schoenoplectus is too fragile to be used in water gardens small enough to permit its shockingly-narrow stems to be touched.  They seem to snap from a slit-eyed glance, let alone an actual hand-to-stem fondling.  You're just asking for trouble to site Schoenoplectus in small water gardens.  Instead, place the colony safely out of reach in the middle of your largest water garden.  With such an architectural presence, it is automatically the star, even in unusually spacious settings. 

Culture

Full sun, planted in heavy soil in a container that's then sited in still water deep enough that there's a single-digit-of-inches of water above the soil surface.  As is typical for aquatic perennials, there's no need to worry about good drainage.  Heavy soil—even clay or subsoil—is just fine; any soil that could be used to pot terrestrial plants respectfully would be so light and fluffy it would be difficult to keep it from washing out of the container.  I dig "potting" soil for my aquatics directly from the subsoil layer of my garden.    

How to handle it: The Basics

Plant in Spring, in a large container that, nonetheless, is still manageable enough that you can lower it smoothly a few inches below water.  Before submerging, mulch the container with small gravel, to hold the soil in place as the water washes over the surface on the way down.  Although Schoenoplectus will also grow with just its feet wet, and with the soil surface above water, the colony is much more susceptible to weeds.  I speak from tedious experience.

 After the stems are killed by frost, cut them to the ground (or, the lazy solution, just to the water level) in the Fall.  If your pond is not in easy view of the house, you could wait until Spring to do this.  Be sure to groom the colony before it returns to active growth, otherwise you'll be doing the job with nail scissors, carefully cutting individual dead stems from amid the fragile tips of the emerging ones.

How to handle it: Another option—or two!

Schoenoplectus growth is dense, both above and below ground.  But the stems are so narrow that there's still plenty of light (and, apparently, root-room) for weeds.  To avoid snapping more stems than necessary, weed the clump ruthlessly in early Spring, as soon as the weeds have emerged from Winter dormancy.  Take advantage of the fact that the weeds, being weeds, are often a bit earlier out of the gate than the reed itself.  Put on your waders and your long underwear, then, to get the job done ASAP in Spring, even when the water is still frigid. 

Next to the waders (and the long underwear), a soil knife is your best friend for the task.  Aquatic weeds tend to have penetrating and strong roots, and often can't be removed by yanking.  Thank goodness:  Any yank strong enough to succeed is just as likely to yank the entire colony's root mass out of the container, weeds and ornamental still tangled together—or cause you to lose your balance and get a full-body dunking.  Instead, use a soil knife to cut weeds out of the soil with calm surgical brutality, like a country vet blithely performing some unmentionable procedure on an animal right out in the field.  (I'm the son of just such a large-animal veterinarian; you have no idea what necessary grizzliness happens out there in the meadow.)  Schoenoplectus fills in quickly, so don't be afraid of the inevitable, that you'll be removing sizable hunks of the root mass of Schoenoplectus along with the weeds.  Fill in the divots with fresh (but heavy) soil. 

Such weeding will have the same effect as dividing the colony, and so will reward you with more vigorous growth than ever.  Such enthusiastically-interventionist weeding is much easier than actual dividing, too, for which you'd need to hoist the entire colony—which could weigh a hundred pounds or more if you plant, as I do, in a galvanized wash-tub—out of the water first.   

Quirks and special cases

The narrow stems are remarkably prone to snapping; try not to handle your colony after its growth has emerged in Spring.  No matter how careful you might be, you'll have to snip off a few bent stems.  For the same reason, site Schoenoplectus as far away from the margins of your water garden as you can.  Visitors are unable to resist fingering—and therefore snapping—the stems.

Downsides

With its fragile stems, the necessity of some down-and-dirty weeding, and the need to cut off last season's stems, Schoenoplectus is likely to draw you into the pond two or even three times a season—four, including the return trip to snip off the stems that, somehow, got snapped despite your best efforts.   

Variants

The stems of 'Zebrinus' have alternating horizontal bands of white and green.  The straight species is all-green.  To my eye, 'Zebrinus' is a stunt and the straight species is a bore.  It's 'Albescens' or bust.  

Availability

On-line and at retailers that feature aquatics.

Propagation

Division in early Spring.

Native habitat

Schoenoplectus tabernaemontani has an unusually cosmopolitan distribution.  I've seen it in databases of natives of Florida as well as natives of Manitoba.  Indeed, the species is known worldwide.  Being native of just about everywhere, then, it's therefore native of nowhere in particular.