Early Spring Cultivation:January to February grow it in the greenhouse or nursery, planting in mid-April in the open ground after the frost. In late May to June harvest. Late Spring cultivation:March to April grow it in the greenhouse or nursery, April may be breeding in the open field. May planting, late June to July harvest. Autumn cultivation:In late June to July nursery. In early August planting in the open field, in late September to October harvest.