A great source of
pleasure to me, is to design and plant out “Theme” troughs. There are many
hundreds of theme ideas if you use your imagination.What about:
Plants from your favourite country
Troughs planted with your favourite colours Single genus troughs Troughs from an AGS/NARGS seedlist selection
Plants of architectural shape Silver leaved planting
schemes Ericaceous only troughs Plants that flower in your birthday week (Well
maybe that’s going a bit too far)
But you get the idea, don’t you?
Let’s have a look
at some of these:
NEW ZEALAND ALPINE
PLANTS IN TROUGHS
There are many beautiful plants from the Antipodes that are
suitable for trough culture and a scheme can be designed to enjoy the colour,
form and architecture of these plants for many a long-lasting season.
Despite what has often been written about New Zealand flowers
being any shade of white, I hope to offer a diverse colour range for your
trough, from yellow buttercups and pink koromikos to blue harebells. Many, if
not all of the plants that are mentioned can be obtained from the seedlist
offered as part of the membership benefits of the NZAGS.
The New Zealand flora has a number of specimen plants to
offer for trough lovers. The Helichrysums, coralloides and selago, make compact, yet stately additions to the
trough garden and are interesting focal points with their “woolly” whipcord
foliage and yellow daisy flowers. Other focal plants include Leucopogon suaveolens (chameleon-like foliage), Carmichaelia monroi ( purple pea flowers)
and of course the dwarf Coprosmas, so exquisite in
their fine berrying forms. (NB: You will need both male and
female plants to induce fruiting). For those of you who have no sense of
pain, there are the “Spaniards” , a most lethal but architecturally handsome
genus of plants. The sword-like leaves are unswerving in their ability to
pierce you where it hurts the most. Beware of Aciphylla horrida, which as its specific epithet
implies is “horrid”. One negative encounter with this and you will never garden
again. A saving grace with this race of thugs, is that it does provide a number
of dwarfer specimens which, although no less fearsome, are small enough to be
avoided with some care. Aa. dobsonii,
spedenii and congesta are
species in this category and well worth their place in a trough but not,
I hasten to add, in a place easily accessible to children.
For cushion plants, you can’t go far
wrong in choosing varieties and species of the NZ offerings. Celmisia argentea, a tight cushion of small spiny
rosettes of silver, needle-like leaves and pure white, sessile daisy flowers
with a golden boss. A real gem for the trough but will probably need protection
from wet winter days. It’s larger cousin C.sessiliflora is equally suitable for a trough and
is possibly easier to cultivate. Pygmaea (Chionohebe)
pulvinaris is another splendid cushion which in England, at least,
has adapted to cultivation without protection and forms dark green cushions,
covered, if one is fortunate, with tiny white flowers.The Abrotanella and Colobanthus species, whilst not as elegant as the
other cushion plants mentioned are, nonetheless, excellent trough plants, the
latter having bright green cushions which can light up a trough on the darkest
of days.
For crevices, there are some wonderful, although extremely
difficult subjects to choose from. Lignocarpa
carnosula is a fleshy plant with leaves reminiscent of a stag’s
antlers in a beautiful shade of grey-blue. The yellow flowers lie beneath the
foliage as though waiting to erupt in a blaze of colour, which of course they
never do but the anticipation is still there. Stellaria roughii is a real tester but worth any
effort to provide it with the conditions it likes and deserves. Scree treatment
is about your only chance and so a high crevice in a deep trough is possibly
the answer (This would also apply to the Lignocarpa). Other plants for a crevice include Wahlenbergia cartalaginea (the fleshy harebell), Swainsona novae-zealandia (with glaucous,
pinnate foliage and pink flowers) and Hectorella
caespitosa (a fine cushion plant also).
For the flat areas of the trough, there are some excellent
turf imitators. Scleranthus uniflorus will
form mounds, hummocks, cushions – you name it- with apparent ease. Agrostis muscosa is a bluish cushion forming grass
(not many of those about) and some of the mat-forming Raoulias, like subulata and tenuicaulis will also spread nicely but in a
reserved manner. One of the advantages of growing New Zealand plants, is that
they, like no others, actually enjoy plant association instead of vying for
supremacy of the soil and its nutrients. Celmisias
and Gentians growing up through Scleranthus uniflorus is not an uncommon site in a
trough. This can of course be made to happen by sowing seeds directly into the
cushions and mats.
For the edges of the trough and to cascade over the sides,
there are some lovely Parahebes,
Raoulias and Pimelias
with a variety of foliage form and colour to choose from. Some of the better
ones are Parahebe linifolia, with dark
green shiny foliage and sky-blue flowers, Raoulia
grandiflora with unusual (for members of the Asteraceae) stellate
flowers and almost saxifraga-like rosettes of silver and Pimelia prostrata with its red stems, grey leaves
and creamy-white flowers.
Many plant lovers have a special affinity with a foreign
country. Perhaps they have visited there, or maybe they have friends or
relatives there, or perhaps it is a special dream to go there one day. If you
have such an affinity with a particular country, then why not have a daily
reminder of that country’s flora by making the effort now, to plant up that
“special” trough garden.
Now what about –
TROUGHS PLANTED
WITH YOUR FAVOURITE COLOURS?
OK, I know it sounds a bit _ _ _ _ _ _ (you are entitled to
enter any word you think adequately describes the topic….but remember, this a
a “family friendly” site).
Think about it though. Everyone has their favourite football
team…mine just happens to be Manchester City (and it took a lot of courage to
admit that). Their colours are sky-blue and white (Campanulas and Celmisias).
Or what about that wedding bouquet with yellow and white tea roses. (Ranunculus and Arenaria) or
the favourite sweatshirt in purple and cream (Penstemons and Aquilegias)….Yes, I know nobody has a purple and cream
sweatshirt but use your imagination.
Follow the drift? Given some thought and preparation, it is
possible to plant troughs to give plants of different colour and contrasts
throughout the season. I would be very interested in what ideas you come up
with.
Now to something marginally more sensible
THE SINGLE GENUS
TROUGH
These can be amongst the most rewarding troughs of all
especially if you want to have colour all the year round. There are so many
genera to choose from: Saxifrages, Primulas, Sedums, Sempervivums, Lewisias,
Arenarias, Campanulas etc., etc.
SAXIFRAGA
There is nothing more satisfying than a trough filled with
saxifrages in spring. They are amongst the most accommodating of alpine plants
with species that will cascade, over the sides of a trough (S.oppositifolia), mound into superb cushions
(Ss.pedemontana, iranica), form tight mats (Ss.georgii, hypostoma, stolitzkae), flower in acidic soils (S.lilacina) and give the most magnificent flowering
displays (S. ‘Tumbling Waters’). The
hybrids too, provide a wealth of colour S.‘Penelope’ (apricot), S.‘Love Me’ (salmon pink), S. ‘Judith Shackleton ‘(white) and S. ‘Ellie Brinkerhof’ (deep maroon). There
are so many ‘new’ saxes coming into cultivation nowadays that the combinations
are endless. Whether large or small, your trough can be a mass of colour
throughout the spring.
PRIMULA
So much depends on the floriferousness of the clone but there
are some excellent trough primulas available through the trade at the moment.
Often short lived (unless regularly divided), they provide good colour during
the spring. Ones to try are Pp minima, pedemontana,
allionii, viscosa, integrifolia, marginata, pubescens and the various hybrids that have been made from these
and are now generally available from nurseries
Just a couple of examples there to encourage you to come up
with your own ideas. Obviously, you will know which plants perform well for you
and these should be your first choice but try those you never thought of…they
may well surprise you. The other side of course to planting a SGT is that you
may very well be rewarded with a brand new hybrid.
TROUGHS FROM A SEEDLIST
COLLECTION
Every year, we alpiners study the seedlists and hope that we
can obtain that which we have sought for many years, or perhaps that which is
relatively new to cultivation or even that which we have grown in the past but
sadly lost.
This next time, why not choose plants that are amenable to
trough cultivation and sow them directly into a trough. This is not as
difficult as it may at first appear. Prepare your trough, complete with
landscaping, including crevices etc. and fill it with a compost similar to what
you would normally use for your seed sowing. Ensure that the compost has
settled well and then just sprinkle on the seed. You will be surprised how well
this works. In fact, I have had success with this method where previously, all
attempts at germination of certain species had failed. Try it with say, 10% of
the seeds you receive and I am sure that you will be pleased with the
results.
SUGGESTED PLANTING
SCHEMES……THE GRAPHICS Trough One
6. Saxifraga x hornibrookii ‘Ellie Brinkerhof’
7. Saxifraga oppositifolia ‘Theoden’
8. Saxifraga ‘Love Me’
9.
Saxifraga oppositifolia x biflora 10. Saxifraga ‘Primrose
Bee’
PLANTS SUITABLE FOR THE
TROUGH GARDEN
The following list of plants has been suggested by Duncan.
Whilst I would not disagree with the validity of their claim to be suitable
candidates for a trough garden, what may be “Suitable in Seattle” (sounds like
a good name for a film that!), may not respond so readily in San Antonio or
Salford. I would advise you therefore to check the hardiness requirements of
the plants you would like to grow, with your local nurseryman. He will advise
you of their suitability for your environment. It may well, in time, be
possible to list a more comprehensive database of trough plants which is
interactive. You know the sort of thing….select a colour, a height, a
flowering season etc. and up comes a selection for you to choose from. This is
quite an ambitious project but as the site is ever-expanding, who knows what
the future will bring. In the meantime you will have to read up in your alpine
books for full descriptions of those listed.
ALYSSUM CAESPITOSUM
ANDROSACE
CARNEA HYB. “LAVENDER GLOW”
ANDROSACE CARNEA X PYRENAICA
ANDROSACE
CARNEA X PYRENAICA “CALLISTO”
ANDROSACE CARNEA X PYRENAICA “JUPITER”
ANDROSACE CARNEA X PYRENAICA “MARS”
RHODODENDRON SALUENENSE SSP.CHAMEUNUM V.
PROSTRATUM
RHODODENDRON “WREN”
SALIX REPENS
SALIX RETICULATA
VACCINIUM MACROCARPON “HAMILTON”
Having, we hope, persuaded you to
experiment with various themes, we think that it’s time to get those seed and
plant catalogues out, or jump in the car and head off to your nearest nursery
and check out the trough plants available. To assist you in your choice, other
articles and listings along this theme can be found on each of our sites at the
following addresses.
The
Trough Garden
Written by The Backyard Gardener
Founder of Backyard Gardener. Sharing trusted, practical gardening expertise and plant care advice online for over 25 years.
