Succulents

Gardening with succulents is quite an alien thing to do in this country, but I think totally logical when you consider it.  Most of the east side of the country, certainly all of the southeast, has long periods with no rainfall and traditional borders suffer badly to the extent that by the time august has been and gone the garden is several shades of brown and nothing else.  As far as the range of succulents is concerned, I believe that the surface has only just been scratched.  Not many pictures yet - sorry !

ADROMISCHUS

Strange little plant that looks somewhere between a moldy grape and a cornish pasty and makes fat little colonies.  The strange thing is that so far this has taken -5°C in my garden with very little damage. (1999)

AEONIUM

I am not certain of this name, but whatever it is called it seems that this aeonium is nearly hardy - at least, hardier than any other I have tried.  It has been damaged, but not mortally, by -5°C in my garden this year. (1999)

OK, I know this isn't even remotely hardy but it is so nice that I have included it anyway.  Trends come and go, every once in a while black is 'in' and this becomes de rigueur on fashionable patios.  And so it should; it is a stunningly beautiful plant that is almost essential for contrasting next to other succulents.  In summer, in full sun, it is such a dark purple that it really does appear black and stick this next to any glaucous grey plant and you have a winner.  Better still a blue such as Agave attenuata, Echeveria elegans or Senecio serpens.  How about a silver such as a dudleya or the humble cobweb houseleeks ?  Not only does it have this great colour, but the stem bears a pattern of leaf scars that is very nearly reptilian in appearance.  Needs to be frost free, if not a little warmer, over winter - when it will actually be growing - and this new growth will remain green until light levels improve again later in the year.  Lovely. 

BESCHORNERIA

Incredibly showy plants from Mexico that are stunning in flower.  In leaf they are very similar to any other glaucous grey-green rosette forming leaf succulents like Yucca gloriosa or Furcraea longaeva, for example.

I haven't seen this in flower, so rely on descriptions that say it is smaller in all parts than the more familiar B. yuccoides, with narrower leaves, an un-branched inflorescence and maybe a touch hardier.  (1999)

Superb plant.  Forms yucca-like rosettes of sword-shaped, glaucous, grey-green leaves up to maybe 1m long and in time will produce many offsets and make a substantial clump.  In spring the centre of mature plants pushes out an amazing inflorescence ; 2.5m long rhubarb red branched stems of dangly green bells.  Wow !  Fairly hardy given a really good sunny spot.  (1999)

BULBINE

Forms a congested colony of grey-green almost allium-like leaves and supplies a never ending progression of orange flowers on numerous spikes.  Hardy-ish - ok here so far (1999)

A meaty fresh green rosette, superficially similar to an aloe but softer, and lengthy spires of yellow star flowers.  Not overly hardy as damaged, but not killed, here by -5°C. (1999)

BULBINELLA

Weedy succulent with bright green allium-like leaves that will seed itself everywhere, but has quaint little yellow starry flowers so I forgive it. (1999)

CALIBANUS

A strange caudiciform succulent that seems to be quite hardy - there are some planted outside at Kew.  When young it looks like a coarse tuft of grey-green grass.  When older it looks like a coarse tuft of grey-green grass growing on top of a tortoise with bad eczema.  Related to nolina etc.  (2000)

COTYLEDON

This is quite interesting.  Overall it looks like a 'money tree' with large oval grey 10cm leaves covered with a mealy silvery patina.  Some forms have attractive red margins to the leaves, and eventually this will grow into a sparsely branched shrub up to 1m high.  Even young plants will produce a few dangling orange bells on a drooping flower spike, which are curious if not outrageously pretty.  It seems quite hardy, and if you are prepared to sacrifice the immaculate silvery patina to rain, is well worth a try outdoors - mine is ok so far through -5°C. (1999)

CRASSULA

This is a neat plant, growing into a small gnarled looking shrublet 60cm tall that is often referred to as looking like a Bonsai, but I personally think it looks like an overweight hebe.  It covers itself with tiny pink flowers for a lot of the summer.  There is a white flowered form around, and I have both wide and narrow leaved forms.  Hardy. (1999)

DASYLIRION

Very attractive race of desert plants from the US and Mexico, sometimes described as looking like fibre optic lamps due to the semicircular domes of very thin leaves made by young plants.  I believe they have enormous untapped potential for growing outdoors in the UK in suitable positions and anyone who has seen the mature beauties at Tresco must surely want to try one at least.  I understand the naming of these to be somewhat arbitrary as the species merge into one another in the wild with no consistent identifying characters.  An acknowledged expert in US desert plants, Dave Ferguson, says amusingly ' The width of the leaf, length of the dried tip of the leaf ("brush"), direction the teeth point, size and shape of the fruit, width of the wings on the fruit, color of the leaf, etc. used to distinguish the various "species" do not work very well.  Sometimes you can even key out four or five species from one plant!'
       

I find this the most attractive species as the leaf tip fray into little tufts giving quite an unusual appearance.  Greener than other species, this has thin leaves edged with teeth and despite what I mentioned above is generally fairly consistent in appearance.  Eventually forms a short trunk.  It is one of the less hardy species at z8, but I have grown mine in a pot for a few years before planting out without any damage. (1999)

One of the hardiest species, typically with backward curving, widely spaced teeth and narrow green leaves, trunk forming.

Typically long green leaves with consistently untoothed margins and in extreme old age forming a trunk up to 3m.  Not one of the hardier species, but possibly hardy enough for this country. 

Another very hardy customer, with very narrow leaves, closely set, forward pointing spines.  Even as a small plant mine is doing very well outside. (1999)

This is the most commonly encountered species in this country and seems to be the main 'reference' species in the US to which the remainder are compared.  Typically these have comparatively wide - up to 2cm - bluish leaves with closely set, forward pointing marginal teeth.  Like nearly all the desert plants it isn't widely grown, but all the reports I have heard indicate it will grow outside with no problems - I have never heard a report of failure. (1999)

ECHEVERIA

Very succulent rosette formers that often cluster into colonies.  Most are extremely tender; inexplicably some seem quite hardy.  As potted plants they are meat and drink to vine weevils which seem to have the ability to sniff out a newly potted plant from miles away.  Fortunately the decapitated rosettes will root again with ease, but it does become irritating.

This is regarded as the hardiest species to cold, but possibly not to cold and wet as my experience with it so far suggests it will carry on taking up water if it is available and some leaves have split.  Other than that it is fine, and quite a prospect as the rosettes of pale green almost translucent pointed leaves are very attractive and larger than many echeverias. (1999)   

This is a lovely little thing, the background picture, that is quick to offset into tight little colonies of powder blue incurved rosettes that flush beautifully with purple during the winter.  The colour is really very appealing and contrasts strikingly well with darker plants.   Hardy here so far. (1999)

EUPHORBIA

Huge group of plants that includes a large number of stem succulents, practically all of which are tender.

This seems to be the exception to the rule.  This South African species is like a dwarf version of the more familiar E. caput-medusa forming a densely branched, dome-shaped colony of stubby stems.  A 2 yr old plant here has shrugged off -5°C with impunity. (1999)

Another 'may be hardy worth giving a go' plant.  (2000)

This is said to be the hardiest of the tree euphorbias, ultimately forming a many branched shrub 3m high, and comes from the foothills of the Himalaya in North India.  Could it be hardy ?  Who knows, but it is worth a try should you ever encounter it.

FOUQUERIA

Another desert plant that has got to be worth trying.  Lovely local name Ocotillo, pronounced 'ock-oh-TEE-yo', this is a wiry shrub that branches from the base and has spindly, very spiny stems that snake upwards.  In the wild the plant leafs out after rainfall, then after a while ditches the leaves and covers itself in bright scarlet tubular flowers.  What it will do here is anyone' guess, but if dry is known to take a fair amount of cold down to maybe -12°C.

FURCRAEA

Attractive group of tender plants, two may just about make it in sheltered gardens.  No-one seems that familiar with them, and the naming is a real confusion - the two below may even be the same species !

Large rosette of glaucous-grey green leaves, eventually forms a small trunk and when mature pushed forth a huge fountain-like branched candelabra inflorescence that has greenish bells dangling from everywhere, and reaches 3m high.  This phenomenal effort is fatal to the plant, which is monocarpic, but when the flowers fade they form small bulbils that eventually fall and carry on the good work.  If this is a different plant to below, it is supposed to be slightly hardier.

Larger in every respect, otherwise identical.  Possibly slightly more tender, but some authorities maintain that all plants of F. longaeva in cultivation are in fact F. beddinghousii.  Whatever I have got in my garden, it has lived through -5°C, albeit reluctantly. (1999)

GRAPTOPETALUM

I think everyone's' granny has a plant of this somewhere; if so bung it outside as it seems indestructible.  When planted out in sharply draining soil it grows far beyond the size reached as a pot plant and really is quite beautiful.  The almost translucent pink grey rosettes seem immune to all weather and the growth remains more compact.  As with echeverias and sedums, to which they are closely related, vine weevil love these in pots - another good reason to plant them out. (1999) 

HAWORTHIA

This is supposed to be the only suspect in this otherwise innocent group of plants when it comes to the crime of growing outdoors.  Haven't tried it yet but will put that right this year.  (2000)

HESPERALOE

A sweet, clump forming plant related to yucca with long narrow dark grey-green leaves that have a frayed margin and that even as young plants will produce a pretty showy loose spike of salmon red tubular bell-shaped aloe-like flowers.  There are yellow flowered forms available in the US but I don't think they have arrived here yet.  Quite a hardy plant and well worth growing plus it is a little more forgiving when it comes to soil conditions. There is another species H. funifera that I know little about other than it is said to be larger and hardier ? (1999)

NOLINA

This is a family of evergreen, grassy looking monocots closely related to dasylirion and yucca.  Sometimes included in the genus is the familiar houseplant Beaucarnea recurvata, and if you picture this you will get the idea of their appearance.  Like this plant, some will form a trunk with that same distinctive swollen base, branch sparingly and at the tips have these dense tufts of tough, very narrow leaves.  Others are stemless, and form clumps very similar to pampas grass - in fact there is a specimen of Nolina texana masquerading as such outside the Princess of Wales conservatory at Kew.  All of the following are very hardy to cold, a couple have shown to be ok in cold with damp, the others just haven't been grown.  All of them are very unusual and showy in flower, all will need tracking down.

This is a trunk former, reaching maybe 3m high in old age and becoming very swollen at the base and with fissured bark along it's length, with narrow glaucous 90cm leaves that fray at the margins.  Another species, N. parryi, is very similar but with bluer leaves that have finely serrated margins.  I don't know of any specimens of either growing outside but they should be well worth trying.

Another trunk former, even taller to 4m, wider longer drooping leaves but maybe not quite as hardy. (2000)

A stemless plant, this looks very similar to pampas grass until it flowers.  The 90cm leaves are dark green with fine teeth along the margins.  I saw a plant of this evidently very happy and about to flower in a garden in Lewisham, South London, and there is one outside at Cambridge Botanic Garden.

Another stemless species, although one source says it grows a trunk in old age.  This is outside at Kew, and I have been told this grows outside in the harsh continental conditions of eastern Europe.  Most sources say N. texana and greenii are synonymous, but I have spoke with someone that has both and says they look different.  (Incidentally, this chap is growing both outside in an area of Germany that gets to -16°C  routinely)  (2000)

SEDUM

The choice of sedums for the dry garden is almost bewildering.  They range from tiny, innocent-looking but rampantly spreading evergreen ones through herbaceous perennials to evergreen shrublets, but in nearly every case are hardy, easy to grow garden worthy plants - as long as they are in the right position.  Never plant the plain species S. acre or S. spurium in a small area or within no time at all there will be nothing else.  Information can be found about most of the commonly available ones in alpine gardening books - I have listed here the ones I think are a little more exotic. 

Or maybe Sedum confusum.  I'm not sure which it is that I've got, but it forms a sprawling mat of bright fresh Granny Smith applegreen evergreen leaves around 20cm high and covers itself with yellow star flowers in spring.  Hardy here. (1997)

This is a slow spreader and has incurved glaucous grey-green leaves - tinged red in cold or drought - that make neat little rosettes that slowly make small colonies.  Quite a neat little thing, not really like other sedums.  Ok, well it is like S. laxum, but that is hardly ever grown.  Very hardy. (1999)

This is nice.  A little tender but worth trying, it grows into a colony of cascading blue-grey rosettes on lax stems and in early spring chucks out piles of frothy yellow star flowers in huge inflorescences.  At time of writing (end of Jan) mine is coming into bud for the first time when grown outside, so I will see how frost proof the flowers are.  (1999)

Great plant.  I looks like a slightly lax version of the money trees in that it has a thick main stem and then branching profusely into a dome-shaped shrublet of evergreen, bright green leaves.  In  spring it has masses of yellow starry flowers, but needs a dry, sunny spot to produce these where it will incidentally grow into a far more compact and attractive plant.  The fresh green colour is a welcome change from the glaucous greys of the cactus patch and it seems to be quite a hardy plant despite the literature on it.  In pots it is a vine weevil's dream, but as usual they seem to leave it alone once planted out.  Every single cutting will root - it will even grow adventitious roots on stems in case you were thinking of taking cuttings.  It is sometimes listed as S. dendroideum, but that is a smaller, tender plant.  (1997)

SENECIO

A huge group of plants included in which are many succulents, none of which are reliably hardy as far as I know.  I list these two as they are nice !

Super plant this, a small, spreading shrublet that has leaves that look like silvery cocoons - being strange club-shaped fingery things (that's pretty specific isn't it) covered in a dense white mealy patina, like you would find beneath the leaves of the familiar shrub Senecio 'Sunshine' but all over.  I thought ' what a lovely plant, I must try this outside' but it has been killed at -5°C.  Never mind.  Keep it in a pot and bung it next to Aeonium 'Zwartkop' for the summer.  RIP (1999)

Probably not hardy, I will try some in the future, but an incredible colour - blue.  A totally blue succulent with blue leaves and blue stems. In fact, very blue.  S. mandraliscae may be encountered and is similarly coloured - blue - but larger.

SETCREASIA

This used to be called Tradescantia pallida 'Purpurea' and forms trailing 30cm stems of gorgeous coloured almost metallic purple 10cm leaves ( irresistible to slugs and snails.  Grow this and keep your hostas intact as they will pack their bags and head straight for this ) which in summer have neat little pink flowers nestling in the end.  Give this a dry, well drained spot in full sun, as it's delicate look belies it tough character.  The first frost will obliterate the leaves completely, but I am reliably informed that it will re-appear in spring.  We'll see. (1999)

update 2000.  It did.

TRADESCANTIA

Another lovely companion for the cactus patch, this has the furriest silver haired leaves, neatly arranged in true tradescantia fashion and held on upright 20cm stems with cute pink flowers produced in summer.  Again, will be deciduous in cold climates, but should reappear from hardy basal shoots.  (1999)   Again, update 2000 - it did grow back.

< shrubs-index-treeferns >