1、 Shape difference

Mustard pimple is about 60-150 cm high. The whole plant is hairless and has a slight layer of powder. The root tuber is conical and about 7-10 cm in diameter. The skin color is white, and the root is fleshy, yellow or white. It will smell spicy

Compared with the former, kohlrabi is much shorter, about 30-60 cm high, and the stem is short. It begins to grow into a fleshy bulb about 2-4 cm away from the ground, which is long oval, oblate or spherical. The skin color is usually light green, purple and green, and the inner meat is white

2、 Blade difference

Mustard pimples have a few basal leaves, about 10-20 cm long. The young ones have a few bristles. The top lobe is wide oval, the top is round and blunt, and the edge will be serrated. The stem leaves are similar to the basal ones, and the upper ones are long and round lancets, full-bodied and sessile

The leaves of indigo are wide, about 20-40 cm long, oval, rectangular, round or oval, covered with a layer of white powder, with obvious sawtooth or notch on the edge