Herewith, a couple of failed experiments at growing outdoors. First, some unknown echinopsis hybrids, which have taken on that horrible pale translucency that non-hardy cacti go when they’ve been frozen solid and snowed on:

Meanwhile, the majority of Cylindropuntia x kelvinensis has merrily turned into unpleasant black mush. I don’t hold out much hope for the recovery of any of the stems that are still green – I think they’re on their way out too:

There are some brave soliders that have got through the rain, ice and snow without batting a metaphorical eyelid – take these two opuntias, both of the same species, although I’m not now sure what that actually is. I think, given the severity of this winter, that it’s safe to describe these plants as completely bullet-proof for growing in UK gardens:

Austrocylindropuntia malyana, or Austrocylindropuntia lagopa as we should now be more correctly calling it, is one of my very favourite cacti. It tends not to be offered for sale terribly often, and when it is, it’s usually grafted onto something like Opuntia humifusa or Austrocylindropuntia subulata, as there is a common conception that it’s hard to grow on its own roots.

I’d venture to suggest that if you try and grow it like a normal cactus (water only from spring to early autumn, allow to dry out between waterings, dry in winter) it’s pretty much impossible to grow on its own roots.

I’m pleased, therefore, to say that the two flourishing specimens above are mine, and, indeed, are ungrafted. It’s not a hard plant to grow, but a few things need to be borne in mind.

It comes from very high altitudes, and experiences cold and wet at the same time. Moreover, if you see photographs of it growing in habitat, huge clumps can be seen overhanging mountain streams and rivers.

That’s the most important thing to know about this plant. Don’t, under any circumstances, allow it to dry out for very long. I keep mine – as you can probably just about see – standing in one of those plastic containers that Ferrero Rocher chocolates come in. I try and keep between half an inch and an inch of standing water in there. The plants are always wet at the root, even in winter, which is when they seem to want to grow most of all, although mine grow all year round.

I haven’t found strong light or high temperatures to be a problem, but I do have strong ventilation in my greenhouse. I’ve heard it suggested that if you can’t provide adequate moving air in your greenhouse during the summer, you’re better off putting these outdoors.

Repotting is something I haven’t tried yet. I’m told, by René Geissler, that it’s best to try and keep the whole rootball intact, and not disturb any of the relatively weak root system. The plant can be lost if the roots are disrupted too much.

As I’m sure many plant enthusiasts do, I bought myself a couple of Christmas presents last week – a couple of rhipsalis from the local garden centre: Rhipsalis cassutha (left) and Rhipsalis micrantha (below).

They weren’t cheap, but they’re super plants, and in remarkably good condition considering the fact that they’ve been living in a garden centre for several weeks.

The Rhipsalis cassutha comes with some interesting (i.e. pretty inaccurate) information and advice. Apparently it is a “robust, trendy plant that can be positioned almost anywhere.” Really? Since when did rhipsalis become trendy? I must have missed that. Even the majority of cactus growers tend not to give them house room. I’ve always liked them, myself, but then I’m odd.

I was amused by the non-commital advice regarding light conditions: “Plenty of light to full sun, but also thrives in semi-shade”. Handy hint: full sun will not do the thinner-stemmed rhipsalis species any good at all. Keep them out of direct sunlight, as they’re forest plants.

The watering advice isn’t really any more helpful: “Water sparingly; once a week is often enough. The plant can occasionally go without water.” Well, yes, sort of. That really doesn’t give a non-specialist buying one of these things anything like enough information to grow it well. Basically, they don’t like being waterlogged, but they don’t like to dry out completely either. They can go without water, but they won’t enjoy it, and will often get the hump if left dry for any length of time.

It’s an age-old problem; nurseries and garden centres like to shift units, so it’s not in their interests to give full cultivation advice – so, if you’ve bought one of these and happen to stumble on this article, hopefully you may have slightly more of a chance with them. They’re lovely things.

Aztekium ritteri

It’s a very tactile plant, extremely rough to the touch, and its wrinkly texture reminds me of the face of poet W. H. Auden in his later years.

I don’t grow this species on its own roots, simply because I haven’t come across a reasonable-sized plant for a reasonable price. I suppose that’s inevitable given how slowly it grows, but it does seem to be the case that one can get hold of a mature plant of Aztekium hintonii fairly easily, but not its close relative. On a graft, like the majority of slow-growing Mexican plants, it offsets far more readily than on its own roots.

My plant is approaching 2 inches in diameter, and is shown here with its beautifully delicate pale pink flowers. It’s grafted on Myrtillocactus geometrizans.

And who’d've thunk it, but they flower too. Here’s Maihueniopsis minuta WG299 putting on a tremendous display. The plant is in a pot that measures 4″ wide by about 5″ deep, and is the first dwarf opuntioid that I’ve grown from a rooted cutting to flowering size.

It’s astonishingly heavy for a relatively small plant: the bulk of it is subterranean. When you see the size of the flower-cup you begin to understand why the plant needs to establish such enormous underground energy reserves before it can set about flowering, and why the majority of buds abort:

I have a good number of adult plants of Leuchtenbergia principis; it’s one of my favourite species of cactus. I’m not sure why, as it’s an unprepossessing, scruffy-looking thing. It’s probably because it has lots of personality.

I found a few years back that the more water I gave them when they’re in full growth, the happier they are.

Giving them a similar watering regime to fraileas generally stops the tubercles drying up and encourages them to flower beautifully. You can’t really overwater leuchtenbergias as long as they’re in a very free-draining growing medium. This plant started looking peaky about halfway through last year, and I foolishly didn’t unpot it and check what was wrong.

Through the autumn and winter, it gradually shed more and more tubercles. When I did get to unpotting it a few weeks back, I realised that it must have lost its roots a good long while ago. I didn’t repot it when I bought it a couple of years ago – and the compost it was in turned out not to be terribly airy, which could have been the cause. There is definitely life at the centre of the plant, and the thickened roots are sound. I’m hopeful that now it’s sitting under artificial lights in a nice warm heated propagator tray it will think about rerooting.

Certainly a cursory lesson in taking notice of what your plants are trying to tell you!

For more information phone Alan Hill on 01142 462311 or email  alanhill3@sky.com

You can join the TSG using the subscription form on the TSG website; if you are interested in opuntias it’s well worth considering.

I’ve adopted a new technique for this. To imitate river-bed conditions, I’ve taken to filling a bucket with rainwater, and submerging them in it completely, until air bubbles stop rising from their growing medium. They’re then left to drain and dry off somewhere shady before being replaced on the top shelf.

They seem to have enjoyed it. There are no immediately obvious casualties, and they have all visibly inflated, suggesting that none of them has failed to reroot after the winter drought.

Has anyone else had unseasonably early trouble with red spider mite this year?

I’m rather pleased that my Echinocactus grusonii seedlings, which didn’t have the best care in their first couple of years, have produced good strong spination which catches the spring light nicely.

They’re in 2 1/2″ pots – well, actually, whatever the closest metric equivalent is – and are much, much spinier than plants of a similar size that are found in garden centres. Why would you want a plant all lush and pumped up with water when you can have something as dangerous-looking as these?

If you’re wondering, the plant growing in the washing powder container below is a cutting of Opuntia quimilo, which produces robust roots very quickly indeed. And spines like knitting needles that appear to never stop growing.

My first year’s worth of juvenile lithops are now progressing well with their second true pair of leaves. These are Lithops julii ssp fulleri, one of three pots of that subspecies from different localities.

Given my disastrous track-record with mesembs prior to the last couple of seasons, I’m really pleased that I’ve kept these going through their first winter.

They are starting to get a little crowded though – I suspect I may have to prick them out in the summer.

Here’s another group shot of seedlings sown between December 2007 and March 2008. You’ll need to click on the photo to get a bigger version of the image to see the detail.

Mammillaria perbella ‘infernillensis’ (two pots on the right) are proving to be really attractive young plants, while the three adjacent pots of Pygmaeocereus bylesianus ‘akersii’ have grown rather better than expected and left me with an awful lot of plants to dispose of!

My home-grown seedling of Ecinocereus viridiflorus is now in its fourth year, due to a rather shaky start in life, owing to my then extremely poor seed-raising skills.

Still, it’s turned out well, and this year it looks as though its first wave of flowering will consist of two blooms. Last year it managed a second flush later in the summer as well.

Cintia knizei‘s single flower bud (below left) coninues to develop well, while it’s nice to see Haworthia cooperi var. cooperi (below centre) and Cumulopuntia boliviana “pentlandii” (below right) putting on some new vegetative growth. Click the images to see bigger versions – apologies for poor photos; the light’s been rubbish today!

• A nice Astrophytum myriostigma that I’d had for a good few years.
• A small gymnocalycium seedling given to me by a friend (I forget the species)
• Two plants of Opuntia bentonii which didn’t cope outdoors in the cold snap
• Opuntia decumbens, already illustrated on here a while back
• Echinocereus ochoterenae which got wet in the cold frame and gave up

I nearly lost both my digitostigmas due to the drying out of their ferocactus stocks, but have rehydrated them in the propagator. One is definitely out of trouble, the other should, I think, be OK. As soon as they’re well, they’re coming off those grafts for rooting.

Excuse the poor lighting of this photo, which was actually taken a little over two weeks ago; it shows new growth already appearing on a Cumulopuntia boliviana “subinermis”. The bolivianas seem to be awake quite early this year; three of mine (yes, that does mean I have more than three clones of Cumulopuntia boliviana - but don’t ask how many!) are already well in growth without any encouragement from the watering can!