It turns out that beetroot, turnips and radishes all transplant well so I’ve sown four or five seeds in a pot and thinned them to a maximum of four in a group. They’re more of a ‘swollen stem’ vegetable than a ‘root’ vegetable. The true roots extend beneath into the soil. I’ve been transplanting clumps of two, three or four of them and it’s working well. I twist out the biggest one in the clump and leave the others to continue growing. These beetroot clumps were 30cm apart in each direction – 16 clumps in a bed 1.2m square so about 40 beetroot. You get a built in succession of harvesting which I like. Not recommended for true root vegetables like carrots and parsnips which do better sown direct.