People either insist on repeating the traditions they had as children, or they detach and reject tradition altogether. On occasion they create new ones, particularly if they start new families or enter a new culture. But new rituals, even after years of diligent practice, will always sit in shallower soil. My childhood was spent in Sweden, and so to me Christmas must always be snowy, dark and eerily quiet. You must have candles in your window, gingerbread men and a real pine tree. There are the stranger Swedish traditions too such as compulsory viewing of Donald Duck re-runs, and opening all the presents on Christmas Eve; but we won't go into that right now.

My parents – a geneticist and a physicist – brought us up to be faithful atheists. On dark nights I would comfort myself by murmuring into my pillow "I believe in science". That's no small feat for a child since the Swedish word for science is unwieldy: "vetenskapen" – literally, "the making of knowledge". Needless to say, the Christian meaning of the season was completely lost on us. We only celebrated it the way we did because everybody else did.

Other than the greed for presents on my part, what I remember most is a cosy family warmth; feeling for once that "all shall be well, and all shall be well, and all manner of things shall be well". What I didn't realise at the time was that my love for mystical rituals was taking root, right under the noses of my family of non-believers. They might light candles and think nothing of it, but I'd stare into them for hours, repeating prayers that I'd learned from fairy tales. I was dismissed as the daydreamer of the family, but the reality was much worse than that. I became religious.

It didn't happen straight away. I loved playing with my parents' work things, even "helping" my mother with her lab projects. But always I harboured the niggling doubt common to those who go looking for religion: I knew that the picture was not complete.

I tried sharing the various faiths of my schoolfriends, joining them in Christian camp or asking about Islam, but they were culturally entrenched too; much as I tried, the shoe wouldn't fit.

Finally, aged 19, I found what I was looking for in Roshi Philip Kapleau's book, The Three Pillars of Zen. It read like a modern-day wizard's manual, with meticulous practical instructions for how to practise Zen, become enlightened and enter Nirvana (at least, that's how I remember it).

It all made perfect sense to me, which is odd considering that I had no background in either Zen or Japanese customs. But unlike my parents, I didn't feel the need to prove things in a science lab. I was more intuitively led, and finally I'd found an ancient tradition that prized and nurtured that skill.

I became a Zen Buddhist, but don't misinterpret this brevity for ease; there were 15 years' worth of potholes along the way. Tender and wiser I came out the other end: a half-Swedish ex-atheist Zen Buddhist in the UK.

Christmas is the biggest ritual of the year; perfect for hijacking to practise Buddhism. I respect local tradition by raising a (plastic, un-killed) tree, going to Christmas carols and getting drunk with my British in-laws.

I also find my own way to express faith. The pure-white tree symbolises "beginner's mind" and in it hang dark red apples, symbolising choice (this isn't necessarily a throw-back to Adam and Eve so much as the Twilight vampire trilogy). The branches symbolise growth and connection.

Next to it, with glitter in his antlers, is my Christmas moose. In the Buddhist concept of Sange, you honour your past and resolve to learn from it. As a teenager I rejected my country of origin, finding it too narrow-minded and homogeneous – but I've come to appreciate its good qualities, and that's what my Christmas moose stands for: a strong and silent grace as it moves through ancient forests. Not all new traditions have to take root in shallow soil; some, it turns out, were there all along.