Brassica oleraceae var. chinensis. Thick, elongated, green leaves grow on long, chunky, pale white stalks (petioles). White Stemmed pac choi have a mild, sweet flavour that works well in salads and stir-fries. Try adding thinly sliced pac choi to any noodle dish, or any vegetable soup recipe. Thin plants to 30cm (12") so that they can grow to full size. White Stemmed pac choi seeds may be grown from early spring to late fall, and the seeds do not require warm soil for germination. This variety forms nice, tight, tall, urn-shaped heads with broad leaves.