Hi Dwayne, kumara can be grown in large grow bags (the ones with the handles on them) 30-50cm in diameter. The key to successfully growing kumara is to keep them shallow, kumara pits have a hard pan below the top soil, the soil is not deeply dug, some home gardeners dig a sheet of corrugated iron down into the pit or soil, so that the kumara do not grow downwards, but go horizontally. The deeper they go, the less kumara on the plants. Make sure the runners and shoots do not take root, keep lifting them up to prevent this. The tips from the runners can be picked and added to stir fries and salads. Use a quality free draining potting mix, Tui Vegetable mix is ideal, it is free draining, contains dolomite lime, sheep pellets, blood and bone and has an organic bark base. Feed with Tui Seaweed & Fish every 2-4 weeks and make sure they are consistently watered throughout the growing season. Harvest once the leaves start yellowing in late March, and before the first frost. For more information check out our kumara growing guide here https://tuigarden.co.nz/how-to-guide/kumara-growing-guide/.