Gardeners of ancient times, before industrialization, had found the solution to the loss of soil fertility: crop rotation, green manure and fallow.
Why sow green manures in spring?
Plants grown as green manure serve as temporary ground covers before being buried in the soil to enrich it with essential minerals for vegetable crops.
- They weaken and smother weeds.
- They prevent erosion, leaching and drying out of the soil by protecting it from the sun and wind.
- They improve the quality and structure of the soil.
- They enrich the soil with organic matter.
- They produce reserves of potassium, phosphorus or nitrogen.
- Their flowering attracts many insects and pollinators.
- They break the cycle of disease.
- They make excellent mulch when left on the surface after mowing.
- They help water seep into the earth when they are buried.
The perfect green fertilizers for spring
Oats — Avena sativa
- Poaceae family;
- To sow as soon as the soil permits (April);
- Mowing: 20 to 60 days after sowing;
- Tolerates all types of soil.
Field bean– addictive faba
- Fabaceae family;
- To sow as soon as the soil permits (April);
- Germination in 3 to 6 days;
- Resists the cold well;
- Tolerates poor or clayey soils and high levels of mineral salts;
- Mowing: 30 to 65 days after sowing;
- Fixes nitrogen in the soil.
The oat and forage pea duo – Avena sativa and Pisum sativum
- Family: oats — poaceae; peas — fabaceae;
- To sow as soon as the soil permits (April);
- Same growth speed, same resistance to cold;
- Mowing: 20 to 60 days after sowing
- Nitrogen fixers, producers of organic matter.
The mustard - Sinapis alba
- Brassicaceae family;
- Decompaction of heavy soils;
- Rare vigor (growth up to 80 cm in one month);
- Appreciable contribution of nitrogen and organic matter.
Phacelia — Phacelia tanacetifolia
- Family Hydrophyllaceae;
- Herbaceous plant native to North America cultivated as green manure or as a honey plant.
- Rapid growth;
- Well-branched root system restructuring the soil;
- Fight against nematodes;
- Smothers weeds;
- Maturities after approximately 3 months.
As a honey plant, it can be sown in spring along the edge of a vegetable garden, for example, and become an intercropping green manure. Its abundant flowers attract pollinating insects and other garden beneficials, such as bees and hoverflies.
Learn more about these good agrarian practices forgotten for too long which can also be implemented in intercropping or in the fall.
