The first of the specials is "Plant Addicts" (13 March), in which Carol Klein meets ordinary gardeners and professional nurseryman who are obsessed by plants, including plant hunter Roy Lancaster.
On 20 March, in "No Grounds for Gardening", Joe Swift looks at gardening without a garden - including roof gardens, vertical gardens and balcony gardens. Both these programmes were postponed from last summer and this January.
On 27 March, in "For Peat's Sake", Toby Buckland investigates the repercussions of the great peat debate. HW 's Peter Seabrook is also featured.
The BBC said: "As the horticulture industry admits it will never meet the UK government target of 90 per cent peat-free garden composts, soil improvers and mulches by 2010, Buckland talks to professional growers and to amateurs."