soil and compost

Our video expert is Blue Peter gardener Chris Collins. He's a qualified horticulturalist and award-winning gardener, who's presented shows on everything from allotments to Chelsea - check out his website for details. He loves sharing his experience with growers old and new!

Gareth Austin is resident gardening expert with BBC Radio Foyle and lectures in horticulture in Northern Ireland. Gareth has made it a prority to encourage gardeners throughout Northern Ireland to 'reclaim the space' and start growing vegetables in any area they can find.

Maria del Carmen Casarrubios is a tutor and practical instructor at Capel Manor College, Regent's Park. She trained at Capel Manor and Writtle College in Amenity Horticulture and has 20 years' experience of working with plants.

Sally Smith is a freelance gardening researcher and lecturer. She headed the advisory team at Garden Organic for many years. Pest and disease control by organic means is her speciality, Sally says: "Managing your soil is key to solving nearly all gardening problems, look after your compost heap, it's your most important asset."

Brendan Little trained at National Botanic Gardens, Glasnevin and Royal Botanic Gardens, Kew. Brendan runs organic gardening courses, works as a garden designer and is in the BBC Radio Ulster Gardeners' Corner team."

Karen Kenny is the Eastern Region Rep for the National Society of Allotment & Leisure Gardeners as well as on the management team of Suffolk and Ipswich allotments where she runs a site. Karen is also an accomplished lecturer on most gardening subjects, including allotments.

Peter Horrocks has an allotment in Newcastle. He's the regional rep for the National Society of Allotment & Leisure Gardeners in the North of England & Scotland, the secretary of the Newcastle Allotments Working Group. Plus, Peter is secretary of a ten-acre allotments site in Newcastle, considered by many to be one of the best in the city.

Ben Raskin is an advisor with the Soil Association, as well as helping to run 22 acres of organic vegetables. With over 16 years of horticultural experience, including running market gardens and working at the Welsh College of Horticulture, he's an expert on organic matters.

Beechgrove Potting Shed is Radio Scotland's top gardening show, giving tips and advice to Scottish gardeners - and the odd Dig In grower - every Sunday.

Zoe tends the Dig In website. When she's not in the office you'll find her gardening on Hampstead Heath and in Regents Park.

Ann "Dig In" Kelly looked after the blog from day to day until May 2010. Bitten by the gardening bug a few years ago, she has progressed from a few growbags to a great big polytunnel. She hates slugs.