Forest Chump

I'm perched uncomfortably on a wet rock, trying to stay warm by a fire that our porters have conjured from a handful of damp wood chips. A dozen of us are sheltering under a blue plastic tarpaulin, which is keeping out most of the rain. A light breeze pushes the flames this way and that, making it impossible to avoid the smoke that fills my eyes and lungs every few minutes. Occasionally a section of bamboo explodes with a report like a rifle shot and, for the hundredth time, Uoc staggers around, miming being shot in the chest. The Vietnamese tea I'm drinking is a weak solution of wood ash and bitter tannins but is at least hot. A minor wound at the base of my spine is leaking a viscous fluid down the crack of my arse in a worryingly unstoppable flow. On the bright side, I'm not yet incontinent so there is no urgent need to wander off into the darkness for a crap in the cardamom.

The joy of camping

In these suboptimal conditions the Hmong porters are squatting, apparently oblivious to the smoke, chatting incessantly about god-knows-what and expertly preparing our dinner. One man chops vegetables and meat with a short, wickedly sharp machete; another tends the fire, feeding it with chips cut from the heart of a fallen tree; a third swiftly whittles half a dozen sets of chopsticks from a length of bamboo. This is the fourth night of the trek and the joint of pork we are to eat looks like it's ready to walk again. Aaron assures me that lemongrass has antibacterial properties but I can't help thinking that a bucket of bleach and a prophylactic course of doxycycline would be more appropriate. Although the meal is a heroic achievement in the circumstances and I want to appear gracious, I eat without enthusiasm when a plate is handed to me and throw most of the meat into the fire.

The highlight of the evening comes when Bleddyn, who has his back to the flames, suddenly yelps and shouts 'Jesus fuck! My arse is on fire!' It isn't, sadly, but we all laugh. He gets his own back later when I discover that I have melted one of my boots while attempting to speed dry it. We are camped near the shelter of a family of cardamom farmers and Uoc jokingly suggests recruiting a couple of the farmer's daughters to help raise our spirits. 'No tits, big smile.' He says and giggles. Declining the offer of a cup of apple wine I ask for a coffee and absently scratch the itch on my spine. A leech the size and consistency of a ripe olive falls into my hand, belching blood (mine). The mysterious leaking sore is explained; leech spit contains a remarkably potent anticoagulant. As the loathsome creature shrivels in the embers, I reflect that at least it has probably stripped my arteries of cholesterol.

We retire to our tents, which have been pitched on a bed of cut cardamom stems. I use a tee shirt to mop up the puddle of water that has accumulated in a hollow in the groundsheet and wriggle, fully clothed into my moist sleeping bag. I decide to read for a while and dig around in my rucksack for David Mitchell's 'The Thousand Autumns of Jacob de Zoete', which I have been saving for such an occasion. It has been sitting in the puddle of water and has swollen to twice its original size. The pages are stuck together and disintegrate when I attempt to peel them apart. I decide that this is a two sleeping pill night and, after a while, drift gratefully into drug-induced oblivion.

Parnassia grandifolia

A few years ago, plant hunting in Tennessee with a friend, I saw Parnassia grandifolia for the first time. It was growing in thin soil on a steep slope. The site is rich in horticulturally excellent woody and herbaceous plant species, including Nyssa sylvatica, various Magnolia species, Aconitum uncinatum and Clematis viorna. Alkaline water seeping from the bedrock makes the soil permanently wet, though the drainage is simultaneously excellent. At the time I was more interested in a colony of Trautvetteria growing beside the Parnassia. The Trautvetteria was in flower (in mid July) and its unusually coriaceous leaves alerted my observant friend to the fact that this might be a new species, a hunch that subsequent molecular analysis has confirmed. Beside this exciting find the Parnassia's foliage, reminiscent of an Asarum, seemed rather insignificant. When it flowered for the first time in cultivation, however, my indifference was replaced by an immediate enthusiasm for the extraordinary flowers, which are bright white, veined with emerald green. The patterns made by the veining remind me of a computer-generated fractal. It is flowering again now, in mid September.

Parnassia grandifolia

Stenanthium diffusum

A few years ago I spent an eventful couple of weeks in the eastern USA, staying with some friends I'd made via email through our mutual interests in various plants. It was pretty brave of them to invite a total stranger (and a Brit) to stay. The hospitality I was shown was extraordinary and the friendships have blossomed, in a way that gardening friendships have a habit of doing.

I was also shown some fascinating plants, including Stenanthium diffusum, which I saw in Tennessee, growing in very wet, acidic humus, in deep shade. The couple of plants that I was given have flourished in cultivation in a shade tunnel in coir-based compost, despite my exceedingly alkaline water supply. This year they have flowered particularly well and I am hoping to harvest a bunch of seed shortly.

Stenanthium is an interesting little genus in the Melanthiaceae (which also includes Paris and Veratrum). The number of species involved is up for grabs and opinions range between one and four or five. Horticulturally speaking there is a huge difference between S. diffusum at the most gracile end of the spectrum and S. robustum (see a superb image of it here - I don't have it yet) at the other.

With any member of the Melanthiaceae it's a case of mi casa su casa but I think that this plant has a particular grace that is sometimes lacking in the more butch members of the family. Eventually I would like to have drifts of it growing beside the stream, paired with Epimedium, a totally unnatural combination that nevertheless works exceedingly well. The plant in the background in the pictures is Epimedium alpinum, a European member of this mainly Asian genus.

The photographs below were taken in very early September.

Stenanthium diffusum

Stenanthium diffusum

The Holy Trinity

'Hi Tom, Bleddyn here. Fancy a trip to Vietnam? Let me know as soon as you can.'

So went the message on my voicemail. Bleddyn Wynn-Jones is the co-proprietor of Crûg Farm Plants (www.crug-farm.co.uk), the world's best nursery, and the proximate reason I currently spend about 18 hours a day tending my plants. In other words, this is all his bloody fault.

About six or seven years ago I started buying plants from Crûg and, as many others before me have discovered, once you start down that road it leads inexorably to financial and moral ruin. At a certain point, having just parted with £150 for a plant of Schefflera macrophylla (look and lust), I joked to Sue Wynn-Jones that if I ran out of money I could always feed the Schefflera to my kids. When she expressed an appropriate degree of horror at this prospect I reassured her that I would never feed such a rare plant to my kids, even if they developed scurvy. The bloody Schefflera died in its first winter but I now have another specimen, bought for me as an anniversary present by my wife, which will see out its days in a greenhouse.

Bleddyn, Sue and the late Peter Wharton had collected the seed from which my plant had grown on Fan Si Pan, a mountain in the north of Vietnam, near the Yunnan border, an area with higher vascular plant biodiversity than virtually anywhere on earth (see map below).

The arrowhead points to Fan Si Pan. Red indicates areas of very high plant diversity

It was to this mountain that Bleddyn was now proposing I accompany him, on a four week plant hunting trip. My invitation had come at the last minute because his original traveling companion had done a bunk. It was like getting a call from God the Father to say that Jesus had pulled a sickie and would I mind doing a stint at his right side. I pretended to consider the offer carefully for the 24 hours I was given to make up my mind before calling back to say I was in. But no harp music.

We are trying to persuade a mutual friend to join us, for at least part of the trip. If we succeed in twisting his arm, I propose christening (no offense) our expedition The Holy Trinity. That would look cool on future labels. Instead of the familiar BSWJ collection numbers, we'd be FS&HG0001, etc.

Biarum tenuifolium subsp. idomenaeum

I hadn't thought about my schoolboy chum dogbreath for some twenty years until a Biarum species I'd collected on Crete flowered for the first time in August last year. For the uninitiated, Biarum is a  genus of about 21 species in the Araceae, related to Arum, Dracunculus, Helicodiceros and Eminium, distributed in the Mediterranean and the Middle East. It attracts dung and carrion flies, Staphylinid beetles and a small but select cross-section of the human species, those with an interest in the weird and wonderful curiosites natural selection has thrown up across the aeons.

Tony Avent, whose nursery, Plant Delights (www.plant-delights.com), is one of the finest sources of unusual plants on the planet had invited me to accompany him and Alan Galloway on a short trip to Crete in April 2010. It was Tony who spied the approaching-dormant, narrow, undulate-margined leaves of the Biarum growing beneath thorny bushes, where the tubers were inaccessible to the ubiquitous and voracious goats that roam the island. I fancy myself a fairly talented plant-spotter but Tony's discovery was a feat of observational prowess sans pareil.

The dry hillside where the Biarum grows

Would you have spotted these leaves in the shade of a thorn bush?

When the largest of the few tubers I collected flowered, I took a photograph and sent it to David Stephens, Croconut-extraordinaire and one of our planet's handful of Biarum specialists. When the plants entered dormancy, in early summer this year, I sent David a couple of tubers, one of which sent up a flower unlike that of any other B. tenuifolium, in that it lacked staminodes above the male flowers.

Perhaps we were dealing with a new species here, David speculated and asked whether I'd take pictures of the plants I'd retained. Biarum inflorescences last only a few days and it seemed I had missed my chance to look for staminodes.

Biarum tenuifolium subsp. idomaeum

One tuber started flowering a clear week later than the others, however, and I brought it home on a Saturday morning, intending to post it to David on Monday for diagnosis. Saturday was a warm day and, when I returned home in the evening and wearily opened the front door I was greeted by a stench suggesting I was hosting the annual Wiltshire halitosis-sufferers convention, hence the instant return to the front of my mind of dogbreath. The association engine in the human brain is a wondrous thing.

Alas David found superior stamininodes on the new plant, placing it within the Cretan subspecies of B. tenuifolium. The chase had been fascinating, however, and I confessed to David feeling the first tugs of a new obsession. 'Please do get sucked in, I need another obsessive nutter to help me understand them.' He replied. He has sent me tubers of half a dozen species, the beginnings of a respectable collection and I look forward to other submerged memories resurfacing as they flower.