Carole Baxter and Calum Clunie provide more gardening tips and advice from Beechgrove Garden. It's a busy time in the garden, with sowing and planting taking place for the approaching summer. The year's first early potatoes get started, and there is a trial of tomato plants suited to windowsill growing.Calum checks on the progress of the variety of supermarket bulbs he bought last year, and Kirsty Wilson starts the first in her series by looking at the selection, care and display of houseplants. And George Anderson provides the first update from his allotment in Joppa.