In case I haven’t mentioned it before, I should tell you that west Wales is, in general, quite a damp place. The average rainfall in our driest month, May, is 55mm and in October, our wettest month, it’s 110mm; throughout the year it rains, on average, about 20 days in every month. Compare that, if you will, to Hertfordshire where my sister lives: May is also their driest month, but they only average 18mm of rain and in December, their wettest month, they only get 36mm, with it raining, on average, about 9 days in every month.

Mosses grow very well in west Wales

All this moisture means that many things grow really well here, lower plants in particular: mosses, liverworts and lichens. Plus fungi… which is great when you want to go out and pick field mushrooms, but less good in the greenhouse. You see, fungi cause all sorts of problems: our tomatoes and pepper plants in the greenhouse always, for example, get Botrytis (grey mould) later in the summer. Since there are no fungicides registered for use in the UK that will treat Botrytis (and anyway I wouldn’t like to use them if they were), the only answer is to try to keep humidity down in the greenhouse and to deal with the spores before any plants go in.

So, every year at the start of the growing season I fumigate my greenhouse. Or at least I attempt to fumigate my greenhouse. And every year I do battle with a sulphur candle.

If you have never encountered a sulphur candle, let me explain: it’s a tin of sulphur granules with a paper wick. You take the lid off, light the wick, close the greenhouse door on your way out and leave for 12 hours. During that time the sulphur burns, producing lots of smoke which penetrates all the nooks and crannies in your greenhouse, ridding it of all sorts of pests. The result: a nice pest and spore-free greenhouse that will be safe to put your precious seedlings in. It’s just about the only ‘chemical’ I use in the garden, but my goodness is it a bother.

You see, whoever designed sulphur candles has clearly never tried to light one. I have never got one to burn successfully on my first attempt. Because the operation is smelly, I usually do it overnight so as not to upset our neighbours. So, at 9pm on Saturday I was outside with the sulphur candle and a lighter. I carefully followed the instructions, pulling the wick up 10mm out of the sulphur granules, lighting it and then beating a hasty retreat (you really don’t want a lungful of sulphur fumes).

Twenty minutes later I went back to check. It had gone out. So, I pulled some more wick up and relit it.

Twenty minutes later I went back to check. It had gone out. There was not enough wick left to relight. So, I soaked some kitchen paper in some old cooking oil, pushed this into the tin and tried again.

Twenty minutes later I went back to check. It had gone out. I repeated the process with a small piece of candle inserted too.

Twenty minutes later I went back to check. It had gone out… and the wax had solidified on the surface. I got an old metal baking tin, put oil soaked paper on the bottom, broke the sulphur up again, sprinkled it over the paper, added a candle end and relit it. Then I went to bed.

In the morning I went back to check. The paper was singed round the edges, the candle had melted and formed a clump and most of the sulphur remained as it was. So, I sprinkled the whole thing with lighter fluid, lit it and left it to get on.

An hour later I went back to check. It looked exactly the same as last time. So, I build a fire: paper, paper sticks, small sticks, larger sticks, some of the sulphur sprinkled over plus a dash of lighter fluid for good measure. I lit it and came in for coffee.

An hour later I looked out and the greenhouse was finally full of sulphur smoke.

In the evening I ventured in… most of the sulphur had burnt, so I considered the greenhouse fumigated and left the window  open for it to ventilate before those seedlings go in.

And the moral of this story? Someone needs to invent a better sulphur candle before next year… please!