macrorrhizosAroids
Few plants evoke the steamy jungle as much as the aroids with their huge leaves and general lushness. A few have been grown outside in the UK for centuries - there are some really exotic beauties on the horizon that may be within reach. There are several aroids that are superb for giving your pond that exotic 'lagoon edge' feel, especially if you dispense with the primulas and marsh marigolds.......
ALOCASIA
I know nothing about this other than a throw away comment from someone who I haven't been able to get back in touch with concerning it's great cold hardiness. Tell me more if you can, please.
*update - probably only a form of A. macrorrhizos - never mind.
Don't know too much about this one. It is a medium sized aroid from China - leaves reach maybe 40cm - that clumps from the base into small colonies and should be able to withstand several degrees of frost.
This looks like a miniature version of A. macrorrhizos, reaching perhaps 1.2m in time, with perhaps even more prominently veined leaves and wavy margins to the leaves. It is rarely encountered but may resist cold.
This is a giant aroid that is almost identical to A. macrorrhizos and should be treated much the same way.
Often seen under the name of A. macrorrhiza ( in my previous catalogues, mainly, as I used the wrong name.... ) but under ANY name this is an exciting plant. HUGE heavily corrugated, shield-like leaves, well over 100x75cm, held upright on stems that are 75cm or more long, and with age forming a 'woody trunk' that can reach 1m or more. In the tropics this whole plant reaches 4m or more high, and the only place it has been encountered in this country until very recently is in humid botanical hot houses. So what is it doing in this list ? It will tolerate cold - that's why. It is grown in areas of the USA such as North Carolina where the winters are extreme - I have been told that it will resprout following lows of -18°C, yes that's -18°C. The only issue in question is whether it needs the summer heat that the plants experience in this region to come back again to it's former glory, or whether it just goes into a gradual decline. With protection of this 'trunk' from the frost and, possibly more importantly, the wet it should be possible to grow this as a perennial plant as you would Musa basjoo. Time will tell - I have planted out a 2m high beauty summer 1999 - it will be an interesting time finding out as this is potentially the most exciting addition to the exotic garden since Musa basjoo became widely available. ( 1999 )
Another rumour. Large cold hardy aroid that offsets and regrows when frozen solid to the ground ? Cross between A. portei and A. odora that has inherited the leaf size of odora with the wiggly leaf margins of portei. Interesting.......
AMORPHOPHALLUS
I haven't grown this yet but feel I should, as it is certainly exotic. The leaves and stems are attractively mottled and the flower, in it's weirdly phallic way, is also a talking point. Should also be fairly hardy.
ARISAEMA
This is an attractive plant for part sun at the jungle's edge, with curiously shaped leaves and a very attractive hooded flower. ( 1999 )
Another I haven't planted out yet, only pot grown, this only reaches it's full potential in the ground and well fed. At 1.5 - 2m high, it is one of the largest cobra lilies and really makes an impact. ( 1999 )
ARUM
Common as muck but still worth growing as general exotic ground cover, the large marbled leaves can reach 40cm on a rich diet.
CALLA
Great for the pond margin, this creeps along and covers the edges with heart shaped leaves. For the exotic pond it is essential.
COLOCASIA
This is a marvellous plant that rewards any kindness with luxuriant growth. It has wide shield-shaped, wavy-margined leaves up to 80cm long that dangle from 80cm or longer stems. It should be possible to overwinter this either by planting deeply in the border or keeping below ice level in a pond, but this may risk losing the main tuber as it is susceptible to rot . To guarantee big leaves you can just dig it up when the frost blackens the leaves and store the tuber dry and frost free over winter as you would a canna. It can be found for sale as a root vegetable in Asian grocers under the names Taro, Eddoe or Dasheen. ( 1999 ) Most of the cultivars below benefit from being grown in warm conditions all year round so they remain evergreen; the tuber doesn't bulk up as much as that of the species and so there is less stored food to carry the plant through a dormant period.
This is a scrumptiously sexy cultivar of the species, chosen for it's dark colouration. All parts of the plant are very dark purple and the leaves look like they have been fashioned from velvet. Hmmm. Not very hardy - at least I don't think so, but as it is new to cultivation in this country and expensive, I haven't risked it yet.
Another cultivar, less hardy than the species, that has maroon backed leaves and dark purple stems. Lovely.
This cultivar has gorgeous dark purple, almost black, velvet-textured leaves that have the veins picked out in fresh green. Very attractive indeed but, like the others, is a slave to red spider mite.
This super plant looks different to the other cultivars. It's leaves are narrower, more pointy on the corners ( sorry to get technical there ) and glossy on the upper surface ( as opposed to the velvety texture of the others ) The stems are more erect, and glossy black. The flowers are also different, with bright yellow spathes.
DRACUNCULUS
Great and different looking plant for a hot spot. Marbled and dissected leaves and a very interesting looking flower with the delightful aroma of rotting corpse. ( 1999 )
LYSICHITON
Essential for the exotic pond margin if you have deep enough soil to do it justice, as the roots will go down a lot further than you imagine. Bright yellow hooded arum flowers appear early in spring ahead of the leaves and if well fed the blotchy, cabbage-like leaves can reach 1.5m long. ( 1999 )
Very similar, slightly smaller with white flowers. All depends on your colour scheme, I suppose. It has been said that there is a hybrid between the two species that is even bigger, but I have never encountered it.
ORONTIUM
Another good pond plant, this lives with up to 30cm of water over the crown. Interesting more than pretty, it has strange club-like flowers and nice glaucous green leaves. ( 1999 )
PELTANDRA
Yet another of the exotic arums to plant in the pond margin. This has nice arrow-shaped foliage which can reach 90cm high in water up to 8cm deep. ( 1999 )
PHILDODENDRON
I know, sounds mad doesn't it. There can't possibly be a hardy philodendron. Well, it looks like there is. The leaves themselves are pretty tough, taking maybe -5°C before collapsing, but the plant forms a 'woody trunk' ( second lot of parenthesis - I don't know what a woody trunk on an aroid is called botanically, do you ? ) which can withstand much lower temperatures. With protection of this trunk ( and kept dry-ish at the roots ) it is possible to keep the plant as a perennial - I know as I have nursed mine outdoors through -5°C as a potted plant and in some US states it returns from much lower. The following spring the leaves start off where they were the previous year, on mine they have reached 1m long this year. ( 1999 )
SAUROMATUM
Encountered as a plant novelty in garden centres as voodoo lily, this is actually quite an attractive plant à la Dracunculus vulgaris with an equally mottled stem and equally smelly flower. It is also hardy-ish, and so can be grown outdoors until a cold spell does it in - which saves all the threats of divorce etc when grown on the mantlepiece as a dry tuber.
SAURURUS
Another pond marginal for the exotic lagoon, this has lovely fresh green leaves and arching chains of fragrant flowers in summer. Grows in a depth of about 15cm of water. ( 1999 )
XANTHOSOMA
An exciting plant indeed which in terms of acreage has the largest leaves of any aroid it is possible to grow outdoors, even if it is only for the summer months. It has the growth habit of Colocasia esculenta in that the leaves hang from the stems and it doesn't form a trunk, but has a leaf shape nearer to Alocasia macrorrhizos , perhaps more sharply pointed on the corners, but even larger ; 2m isn't out of the question. It is here that something else enters the equation, as I have been told by my sources in North Carolina that his plants have recovered from winter lows of -15°C, which is MIGHTILY interesting. Has recently become available from certain stockists.
Not remotely hardy, but gorgeous, triangular, coffee table-sized leaves with a purplish tinge and purple stems. All round a superbly, scrumptiously, sexy plant.
ZANTEDESCHIA
The familiar florists arum, grown everywhere and for a very good reason - it is a terrific plant. If well fed it can get pretty big as well - it is easier to do this in a border than in a pond, where it will grow equally happily - reports of over 2m high with leaves 70cm long have reached me. There is a lot said about the selected cultivar 'Crowborough' being the desirable hardy form, and everyone that sells it says that is the one they offer, but I'm not sure. ( 1999 )
This is either larger than the type species or smaller, either more attractive or horrible, and either hardier or more tender - all depending upon which books you read. I don't know, as I haven't grown it, but I do like the flowers.
This is a pretty thing, smaller than the preceding plants, more tender, with opaque 'windows' in the leaves giving the appearance of white spotting. The flowers are yellow and very nice indeed. I have yet to test the hardiness, but it should only be a little more tender than the above.