Use organic fertilizers and composts when possible. Kale particularly likes fish emulsion and compost tea. Be sure that you sow seeds two to four weeks before the last frost date if you are planting directly in the garden. If the plants start to crowd each other as they grow, you can always further thin the plants out to allow for more space between each plant. Kale seeds are small and can only grow through ¼ to ½ inch (6–12 mm) of soil. Space the seeds about three inches (7.5 cm) apart. Pat the soil lightly to cover the seeds. While the seeds grow, allow the top layer of the soil to dry out between watering. At this point, your kale seedlings should have at least four developed leaves. It takes four to six weeks for your seedlings to reach this stage.

How would you rephrase that briefly using Chinese?
在至少15厘米见方大小的花盆里将肥料及泥土混合，要尽量用有机肥及蔬菜肥。 此外，你也可以一边播种一边施肥搅拌泥土。 种子要埋在1厘米深的土壤里，种好后轻轻拍平土壤，将种子盖起来。 彻彻底底浇一次水。 等甘蓝长到7-10厘米高的时候就可以移栽了。