Look back in awe: The horticultural hits of 2013

It's a sad indictment. But true I fear. When gardeners gather together, the chat is much more likely to be about disasters than delights. Perhaps we think it would be showing off to talk up our asparagus, or praise our peonies. We scarcely ever do. Instead, we talk like the problem page of Which? Gardening: "My peony 'Bowl of Beauty' refuses to flower." "My lawn has been invaded by dove's foot cranesbill." "Last year I had terrible problems trying to get my beefsteak tomatoes to set..."

We worried ourselves sick over news of a New Zealand killer earthworm that could gobble up British worms in a scenario that sounded more like a low-budget horror film than reality. Despite the fact that our native worms are still quietly going about their business, ungobbled, I expect we'll still lash ourselves into a frenzy about the next 'foreign' invasion. I plead very guilty, having written regularly in this column about Problems and Pests.

So in a determinedly upbeat mood, I'm going to end the year by listing the Five Best Things that happened in the garden this year. If I'm lucky, they might even happen again.

The snake

I know he's with us, because he leaves us his skins, gorgeous parchment cast-offs that sometimes lie right across the path up the bank. In fact, it's probably a she, because each year, we unearth the spent skins of snake eggs laid in the compost heap, each one carefully slit by the baby inside to release itself from its wrapping. Usually, I see only the disappearing tail of the snake itself. It is sensitive to vibration and must hear me coming. But on a happy day this summer he/she stayed, basking on top of the compost and I watched it for some time, 120cm/4ft gracefully coiled, superbly camouflaged. I scarcely breathed during the whole encounter.

The taste of fresh peas

Too quickly this moment is over, but at least (unlike the snake) it is a moment we can recreate. Over the years, I've tried 'Early Onward', 'Hurst Green Shaft', 'Kelvedon Wonder', 'Feltham First', 'Minnow', 'Hurst Beagle', 'First Early', 'Douce Provence', 'Spring', 'Markana', and 'Bingo'. My favourite remains 'Hurst Green Shaft', a main crop pea that produces wonderfully fat pods with superb flavour. If you sow in batches between March and early June, you can extend the crop from late June to September.

Yuksom arisaema

We've been to Sikkim three times already and will be there again next autumn. From Yuksom there is a world-class walk (just a day-length) that takes you on tracks through the forested foothills of the Himalayas to the monastery at Tashiding. There are orchids and waterfalls, but what I most like about this walk is the way it winds you into Sikkimese lives: drinking tea with the woman who spins and weaves the rough wool of hill sheep (I brought some back and knitted indestructible socks); the herdsman driving his two cows to pasture. On our return, I found wedged in my boot soles, some seeds – and sowed them. This spring, up came arisaemas, one of my new passions (think of a native wild arum on acid). Which arisaemas? When they flower, I will know. But the joy is to have such a potent memory of that superb walk here in a cold frame in Dorset.

The snowdrop tree

Beautiful Halesia carolina (mine is one of the Monticola group) is one of many reasons I am drifting away from perennials and towards shrubs and trees. It was planted five years ago, has now found its feet and produces in May a gorgeous show of small white hanging flowers, shaped like snowdrops. It's making a tall, light-limbed, rather slim tree with striated bark, one of "the best things I've never grown before" that we've introduced to the garden.

The scent of Magnolia wiesneri

This was the third magnolia I planted (there are now 11 in the garden) and it remains my favourite. The flowers, borne upright on the branches, open very slowly, dropping three ivory petals, then another three in tantalising stages. I visit it every day in season (late June), until finally it reveals its crown of crimson stamens. Then it releases a scent that is the best smell you will ever get from a garden: celestial lemon with a whiff of pineapple.