Euphorbia tirucalli
A slightly odd plant today. So what’s new I hear! This is a greenhouse/houseplant in Northwest Europe and is not frost tolerant. Even so, it is a very easy plant to grow, being extremely tolerant of drought. Euphorbia tirucalli is from East Africa northwards to the Arabian Peninsula and is grown in India where it is used for hedges, growing quickly when given reasonable moisture. It is upright in habit, with drooping smaller twigs, tiny leaves that drop soon after they form, and inconspicuous yellowish flowers. When growing strongly it is green throughout but when stressed the new shoots flush orange. In frost-free, arid climates where it is grown as a garden shrub it seems to be most colourful in autumn, when chilled, which could explain why mine is looking so splendid. It is a warm-climate equivalent of cornus ‘Midwinter Fire’. It is a shame it is not hardy because here, surely, is a plant that is 100% deer and rabbit proof.
It was named by Linnaeus and the specific epithet is derived from ‘tiru’ meaning good in Malaysia and ‘kali’ being the name for euphorbia, in reference to its medicinal qualities – though these are now debatable. There is a cultivar called ‘Sticks on Fire’ or ‘Fire Sticks’ that has been selected for its bright colour and when you see photos of arid gardens where it is used for ‘xeroscaping’ it looks amazing. So, many years ago, at a flower show, I saw a plant on a cactus and succulent stand and had to have it. Although it was only about 20cm high and cost a blistering (more of that later) £20 I had to have it. Over the years I potted it on and it grew like crazy, every year producing one or two new, very vigorous upright stems from the base to add to its height. Eventually, by the time of the move here, two years ago, it was 2m high. In the wild, or in suitable gardens, it can easily reach double that height.
One thing that rapidly became apparent was that my plant was not ‘Sticks on Fire’. It remained stubbornly green and though its mass of unruly stems was interesting, it was not the most exciting plant I had ever grown.
I would have brought it with me, though I have no idea where I would have kept it for 2 years till the house was done, except for the fact that this is not a very friendly plant.
All euphorbias have sap that contains latex and is toxic to some extent. It is curious that some euphorbias are eaten as vegetables after careful treatment, and the good old poinsettia (Euphorbia pulcherrima) is among the least dangerous. But E. t is among the most dangerous with sap that can cause blindness if it gets in the eyes, skin blistering and rashes and is generally not a good thing to have around if you are likely to come into contact with the sap. I had to get the removal men (they were both men so I am not being sexist) to hump some pretty big plants (though we helped) and I thought this was just a step too far. So on the day of the move I snapped off a few stems about 30cm long and threw them on top of a box of plants. Many weeks later I eventually potted these, by now well wilted, and they had to cope with some neglect on a sunny windowsill for the best part of 18 months. I repotted the fledgling plant this spring and in June it went into the new polytunnel where it was subjected to more abuse and full sunlight for the first time in years!
So now the question is – is this ‘Fire Sticks’ after all? Was all that green in its previous life because of lack of light? My gut reaction, of course, is to be pessimistic and decide that it is not. But just maybe it is. Now that it will be living in the conservatory, perhaps it will revert to green or have just a hint of colour. Some descriptions of ‘Sticks on Fire’ say it is devoid of chlorophyll entirely so the fact that mine is green, at times, suggests that it is not that plant.
Either way, it will now have room to grow and achieve a size close to its potential. I like this plant for its ease of growth and unusual habit. If the colour remains then it is even better. It is not something that I would recommend without reservation. To have such a dangerous plant in the house is, perhaps, a bit like letting your pet python sleep in your bed. But it is such an interesting plant. It has been investigated as a source of rubber, which failed because of high levels of resins in the sap, and also as a bio fuel, so perhaps its day will come. But, for now, it entertains me for very little attention and worry, and for that I am grateful.
This has become very popular for the striking foiar color in landscapes in Southern California. The green form had always been around. It was known simply as ‘pencil cactus’.