(1) Red Acres. Red mu purple kale is a medium maturity variety introduced from the United States. The plant is large, strong growth potential, development degree of 60-70 cm, about 20 outer leaves, leaf color deep purplish red. The ball is tightly packed, and the leaf ball is nearly spherical. The weight of a single plant is 1.5-2.0 kg, and the yield is 3000-3500 kg per 667 m2. It takes about 80 days from planting to harvesting, with a density of 2,000 to 2,200 plants per 667 meters 2. Red mu can be cultivated in greenhouses, improved sun beds, plastic greenhouses and open fields, and its cultivation mode is shown in Table 2.

Table 2 Red mu cultivation mode table

(2) Zi Gan 1. Purple Gan 1 is an excellent variety selected from the purple kale varieties introduced from abroad. The plant is larger, with stronger growth potential, with a spread of 65 to 70 cm, 18 to 20 outer leaves, purple-red leaf color, and covered with more wax powder. The leaf ball is round and spherical, the weight of single ball is 2-3 kg, and the yield is 3000-3500 kg per 667 m2. It takes about 80 to 90 days from planting to harvesting, and its storability and disease resistance are strong.

Zi Gan 1 is suitable for spring protected and open field cultivation, and the planting season can refer to the red mu variety.

(3) Early red. Early-maturing purple kale varieties introduced by the Netherlands. Plants of medium size, strong growth potential, spread degree 60 cm × 60 cm, outer leaves 16 to 18, leaf color is purple-red. Leaf ball is ovoid, the base is smaller, single ball weight 0.75 ~ 1.0 kg, per 667 m 2 production 2000 ~ 3000 kg, from planting to harvest about 65 ~ 70 days.

Early red purple kale is suitable for spring and fall protected and open field cultivation, sowing seedlings from mid-December to early February, planting from mid- to late February to mid-April, and harvesting from early May to early July, with a plant spacing of 50 cm square.

(4) Jumbo Red. Introduced by the United States of America, medium maturity purple kale varieties. Plants large, strong growth potential, development degree 70 cm × 70 cm, 20 to 22 outer leaves, leaf color deep purple-red, leaf ball round slightly flattened, diameter 19 to 20 cm. The weight of a single ball is 2.0 to 2.5 kg, and the yield is 3500 to 4000 kg per 667 m2. It takes 85 to 90 days from planting to harvest. Storage resistance is strong. The planting density of 2000 to 2200 plants per 667 meters 2.

The giant red stone is mainly suitable for spring and fall open field cultivation, spring open field cultivation can be from late December to early January the following year sowing, planting in mid- to late March, plant spacing 50 cm × 60 cm, harvesting in mid- to late June. Autumn open field cultivation in June in the middle and late sowing, planting in late July, late October can be harvested. The amount of seed sown per 667 meters 2 is 50 grams.

(5) Chisel Red. Introduced by the Netherlands purple kale varieties. Plant growth potential is medium, the degree of development of 60 ~ 65 cm, the outer leaves are 16 ~ 18, leaf purple, wax powder, leaf ball is ovoid, the base is smaller, leaf ball tight. Single ball weight 0.75 ~ 1.0 kg, per 667 m 2 production in 2500 kg or so, from planting to harvest about 65 ~ 70 days. Chisholm red purple kale is suitable for spring and fall protected and open field cultivation.