"When the green goes out of the grass" is an old Devonian saying. It means you should start flyfishing for sea trout when the colours of the undergrowth drain into the coming night and this shy fish, difficult to catch by day, starts rising and feeding. My fishing instructor David and I are standing in waders in a peaceful pool while bushes on the bank opposite blend into the dark.
The 300-year-old Arundell Arms Hotel in Lifton, Devon, is the perfect place to go if you want to get to grips with fishing. On the nearby River Tamar and its tributaries, the Lyd, Lew, Wolf and Thrushel, the hotel owns 20 miles of private fishing water, set in woodland and fields with long, placid pools, streams and gravelly runs. Its owner, Anne Voss Bark, recently won a Lifetime Achievement Award for Services to Angling.
Once we have been kitted out with rods, hooks, reels and lines, Roy, chief instructor and Welsh Open fly-fishing champion in 1970, drives me the three minutes to the excellent training ground, Tinhay Lake, stocked with brown trout. First I learn the basics. The "overhead cast" uses a flicking motion to whip the line over the water, making the fly land gently where a large fish would seize it. Or that's the theory. I am more lion tamer than Brad Pitt in the film A River Runs Through It.
"Slow it down," is David's advice. I do and that afternoon we progress into the grounds of Lifton Park, another short drive away. Lush fields slope down to a "beat" on the River Lyd. Using a famed fly called the Coachman, my casting gains both in rhythm and success. Admittedly, a two-inch fish is hardly breaking records, but it is a first in a long tradition. Izaak Walton, author of The Compleat Angler, was doing this 350 years ago. There are sea trout, brown trout and the odd salmon, and it is hard not to feel soothed by the murmur of water slipping past banks of wildflowers. We try another idyllic pool, where a kingfisher appears and a couple of trout leap mockingly. We end the day with the Double Spey Cast, a more complex manoeuvre.
The following night at dusk, David and I head to a still pool to practise night fishing. A trout splashes theatrically and I catch a tree. At a second pool, we descend a wooden ladder, wade quietly out and begin casting. As the night deepens, the stars emerge and the only sounds are the burble of the river, the click of two reels and the swishing of lines. "Shall we go and have a pint?" a voice finally asks some hours later. The teasing trout have long since stopped splashing and a bottle of Cornish Coaster Ale at the hotel bar is easier to catch. Ascending the ladder, we happily rework the disclaimer at the end of A River Runs Through It - "no fish were harmed in the making of this evening".
Marcus Waring travelled with First Great Western (08457 000 125, www.firstgreatwestern.com) from London Paddington to Exeter St David's. He stayed at the Arundell Arms at Lifton (01566 784 666, www.arundellarms.com). The hotel's four-day beginners' course ends with a night-time session. The trout season runs from spring until 30 September, while the salmon season ends on 14 October. May, June and September are all good months for fishing. Tinhay Lake is available year-round. Tourist information: 0870 442 0880, www.visitsouthwest.co.uk)