Plants of this multispecies family are characterized by high vitality. Most ruderal plants belong to it. If, as a result of breeding procedures, it is possible to combine and consolidate the beneficial features of these plants, then we will get a new one, valuable forage and green manure varieties. Cruciferous plants require abundant nitrogen fertilization. By producing a large amount of green mass with a favorable carbon-nitrogen ratio, they contribute to the retention of nitrogen in the matter cycle. When legumes grow poorly in the garden, mostly due to a lack of phosphorus in the soil, they can be replaced with plants from the cruciferous family, on condition of abundant nitrogen fertilization of the soil. These plants are prone to a dangerous fungal disease - cabbage syphilis, which attacks the roots, especially plants on acidified soils. Growing cruciferous seeds, even on slightly acidic soils, requires careful care and compliance with the rules of rotation.

White mustard (White mustard) It grows very quickly and is suitable for both forecrop, and aftercrop. In the garden, the yellow seed variety is the most widely used. Sowing seeds and caring for plants is not a major problem. If we sow seeds in late August and early September, strong plants will grow until late autumn, the roots of which densely overgrow the top layer of soil and which die after the arrival of the first heavy frosts. Thus, at the end of winter, the soil is almost ready for sowing and it is enough to loosen it slightly in spring. If we sow seeds in early spring, we can do this, as recommended by G.. Frank (1978). Sow mustard seed in each free bed or piece of garden. Due to their rapid germination and vigorous growth, the plants shade the soil surface in a short time, which improves its structure. Before sowing or planting new crops, you can shallowly mix the mustard with the soil or use it for mulching.

Oil radish (Raphanus satus) it can be useful for our garden due to its very strong root system. It does not always freeze in mild winters; has high fertilization requirements.

Rape (Brassica napus) it is also quite resistant to low temperatures; in spring it should be carefully mixed with the soil. Some species of plants grown for green manure can be mixed with each other. A mixture of mustard seed with spring vetch or peas is very valuable. A mixture of mustard seed with oilseed radish (2/3:1/3) at the same time gives a lot of leaves and roots.

Facelia (Phacelia tanacetifolia) belongs to another family, namely to the facelias (Hydro-phyllaceae). It is one of the best honey plants and therefore it is very popular with beekeepers. Recently, it has been used as a fodder plant, but as a green manure plant it has not yet gained proper recognition. It has low soil and water requirements, therefore it can also be cultivated on dry soils. However, moderate fertilization is recommended. It then produces a lot of green mass, therefore it inhibits the growth of weeds.

Phacelia is best grown in summer, np. after early potatoes or peas for green grain. The last sowing date is at the end of August. It is not recommended to sow seeds in the spring, because phacelia will not have time to produce a large mass by mid-July. Phacelia can also be grown in mixtures with oilseed radish, I like and seradelą. Its resistance to autumn frosts should also be emphasized (do -7°C).