When I moved to London, my husband Henry gave me a copy of Kate Fox’s Watching the English: The Hidden Rules of English Behaviour. He was hoping the gift would avoid an awkward conversation about our cultural differences. As an American, I cannot think of anything more English than that.

Fox’s chapter about introductions bothered me. The brash American approach: ‘Hi, I’m Bill from Iowa,’ particularly if accompanied by an outstretched hand and a beaming smile, makes the English wince and cringe. I had never known friendliness to be cringeworthy. I felt sorry for Bill from Iowa. I pictured him arriving in my neighbourhood and being scorned for enthusiastically introducing himself to strangers.

Henry tried to explain. ‘We don’t talk to neighbours. Maybe people in the country do, but not Londoners. In fact, I’d say people move to London just so they don’t have to talk to neighbours.’

I could not get to the bottom of this misanthropy. So eventually I stopped seeking answers and accepted Henry’s words as fact. At the same time, I decided to keep the American spirit of neighbourliness in my heart. I resolved to knock on strangers’ doors and introduce myself while offering them slices of buttermilk chocolate cake. Because seriously, how else do you meet people?

The house opposite ours boasted the prettiest front garden in the neighbourhood. Passers-by would stop and Instagram or, when they thought no one was looking, pick flowers. The creator of this horticultural masterpiece was Sam. When we moved in, Sam was busy in his garden. His handiwork was visible from most rooms in our flat. I introduced myself to him and brought him a slice of cake. Henry gave him a bottle of wine. Our toddler stroked his cat. Sam seemed pleased, though painfully shy. He barely made eye contact. For the next few months, we would wave hello to Sam whenever we passed him on the street. He would return our greetings but never our gaze. He only looked at the flowers around him or the dirty blue Crocs on his feet.

On Christmas Eve, as my family walked home after an excursion to the pub, Sam ran out of his flat waving an envelope. It was a card for our family with a red-breasted robin on the front. We thanked him for it and asked about his plans for Christmas. He said he was going to be on his own because he didn’t want to leave his cat. He sounded lonely. We couldn’t help but invite him for a drink at ours.

At five o’clock, when we were expecting Sam, we could see him standing in his window stroking his cat. At 5.30 he was doing the same. Eventually the buzzer rang.

We did our best to serve Sam not only Stilton and tawny port but some yuletide cheer. He didn’t say much, though he did mention problems with his downstairs neighbour, a 70-year-old man whom he accused of playing the radio too loud. We thought nothing of it and offered him hazelnut biscuits.

Our daughter danced to a Top of the Pops special. She showed Sam her books and introduced him to her toys. Some of her teddies gave him kisses. Before Sam left, I gave him a sack of dark-chocolate almonds with a red satin ribbon. He pulled me into a bear hug and smiled. I wished him a happy Christmas and told him that if he ever needed a break from his neighbour’s noise then he should pop round for tea. I thought that a very correct, English offer.

In the months that followed, Sam would show up unannounced and invite himself in. He would sulk in our kitchen and complain about his neighbour. I would offer him cups of tea but he said he didn’t like my tea. Later he would tell me that he didn’t like tea at all. So I brewed coffee and made supportive noises as he moaned.

The only thing that would snap Sam out of a mood was my Sarah Raven catalogue. Sarah Raven is the Martha Stewart of English gardening. If you want to buy Genoa zinnias or master floristry in a weekend, she is your woman. Sam would sit cross-legged with her catalogue on his lap, flipping pages and dog-earing the ones he liked best. Tulip collections, perfect perennials, stunning alliums. He wanted them all. He also wanted to know whether I put edible flowers in my salads, because he was thinking about planting a bed.

After a while Henry gave Sam his mobile number, hoping this would curb the unannounced visits. It did not. Sam’s surprise visits continued until one night he had a mini-meltdown at ours. I was bathing our daughter and Henry was catching up on work emails when Sam came in, insisting we didn’t like him. We assured him we did. Then he apologised for being insecure. Again we told him it was all right. Neither of us wanted to upset him. Sam became frantic, like a bird trapped in a house. Abruptly he left. Henry and I agreed that we had to create some distance.

Then one night Sam woke the whole street by howling at the full moon around 4 a.m. Henry and I assumed he was drunk. Then Sam started shouting that only he knew the truth and would somebody please help him. It went on for 20 minutes until the cops arrived and took him away.

Sam has not been home since. The following day, the police and several neighbours paid me a visit. They told me that Sam had tried to drop an axe on his neighbour in the dark from the top of the staircase. He had missed. Locals had already nicknamed him the Axeman.

After being carted off by the police, Sam called or sent text messages to Henry almost daily for almost two months. Henry never replied, though Sam begged him to call and expressed a hope that ‘everything is still cool’. At one point, his messages took the tone of a jilted lover. ‘You don’t have the heart to call me!’ was the last he sent before Henry changed his number.

Sam’s flowers have died. Grasses have grown tall and weeds have moved in. The garden beds look as if they were sown with malice.

My poor husband is somewhat scarred by the ordeal. I can’t blame him. He gave me a book outlining the rules of English social protocol and I ignored them. I invited the Axeman to tea.

Still, for all that’s gone wrong, Henry and I have met four great people on the block. Our world is a little bigger. For that I am thankful.