We’re an arable farm on the border between Chiddingstone and Penshurst, not far from Tunbridge Wells and Sevenoaks in Kent. Hops have always been grown on the farm but when I bought the brewery and started brewing in 1986, the hopping – ironically – had to lapse. Between farming and getting the brewery off the ground, I just didn’t have enough time.

About four to five years ago I decided to start hopping again because I was having difficulties sourcing the hops I wanted to use from elsewhere. I still had four acres of wirework and poles out there, so I replanted the hops, and we’ve been using our own in our beers ever since. We grow three varieties: Early Choice Goldings, Bramling Cross and Whitbread Golding. Each has a different aroma, and we use them in different amounts in each of our beers.

Hops are perennials. We harvest over two to three days in September, when family and friends come along – it’s a lovely day out, with lots of tea and biscuits, and then we all have lunch together. There’s lots of homemade fare, with produce from our farm – shepherd’s pie, peas, beans, crumble, custard, cheese, and as much wine and beer as you can drink. Which isn’t that much really, as everyone’s pretty tired by lunchtime; a couple of glasses and they’ve had it.

Bob Dockerty: ‘I’ve been doing this for 20 years, and I know where headaches come from – no one gets a headache from my beer.’ Illustration: Michael Thomas Jones/Guardian

We have a hops-picking machine, and tractors and trailers. We bring all the hops back up to the farm and dry them out on the kiln, with big fans blowing heated air until about 10pm. The next morning we finish them off, then lay them out on the cooling floor – which is the wooden floor upstairs – to cool them down so that they keep their colour and retain their bitterness. This is so that they can balance out the sweetness of the malt. Once the hops are cool, we shovel them up with great big scuppets into the press to get the air out, a bit like pressing wildflowers, to preserve them. The hops are squashed into a hop pocket – a large sack – which, when full, weighs about 75kg. Our four acres of hops yield about 12 pockets. Once pressed and pocketed, we bring the hops around to the brewery.

Every year we have new crops of barley and hops, and the challenge is to make the same beers and not give our customers a big shock with new flavours! So we have to introduce the fresh hops very gradually into the brewing process.

In total, we make five beers including our Traditional standard bitter (3.4% ABV), a very sensible drink; our Platinum Blonde, which we do in the summer (3.6%); our Best Bitter and our strongest at 4.4%; and then, in the winter, we have our Porter (5.2%), a London-style beer to be taken seriously; and lastly, our Green Hop Best (4%), which is brewed on harvest day, with hops straight from the fields that aren’t dried. We’ve just finished bottling it and sending it out to the pubs. People enjoy it as a one-off – it’s only available for about 10 days. It’s an astringent, surprising drink.

The brewery is in the farmyard, and there are four people there working with me. We make whole, organic beer, and we don’t use any sugar. All the sweetness comes from the malted barley. I’ve been doing this for 20 years, and I know where headaches come from – no-one gets a headache from my beer. These days I have to take it steady – I had a triple bypass earlier this year and I can’t lift anything. It was quite an ordeal, but luckily I’m made of stern stuff. And most importantly, I’m still drinking our beer.