Alfalfa is a member of the legume family, which is often grown commercially as a forage plant for livestock. That’s because it contains valuable vitamins and minerals that are returned to the soil when the plant breaks down. Alfalfa seeds are sown over bare ground from April to July. It takes about 10 weeks for the plants to mature enough, ready for digging back in or they can be left to overwinter and then turned in a few weeks prior to summer planting. It grows best on free-draining type soils and is excellent for replenishing nitrogen. It is quite a deep-rooted plant so can reach minerals deep down and bring them to the surface layer where they are most needed. Sow at 2.5 grams per sq. m. - this packet covers 40m2 | Alfalfa Green Manure Seeds Sowing Guidelines | When to Sow Seeds: | Apr, May, Jun, Jul | Germination Temperature: | 12C + | Cover Seed: | Yes | Time to Germinate: | 7 Days | Seed Coverage | 2.5g / m2 | |
Green manures provide a cheap, economical source of composting material and are good as a soil improver, as well as reducing weed establishment in ground that would otherwise remain empty.
Ground preparation and seed sowing
Green Manures can be easily incorporated into a crop rotation programme. Clear the area of any weeds and debris from a previous crop of vegetables. Cultivate the area by digging or use a rotovator if it’s a large area. Rake the cultivated ground to a level surface and then firm by treading or use a garden roller.
Lightly rake the surface again and then sprinkle the green manure seeds over the prepared area. If you want a good ground cover to suppress weed growth then sow thickly. Finally, rake again lightly to cover the seeds and water if necessary. Then leave the area alone until the seeds have germinated. If the weather is dry then lightly water as required.
Incorporating the green manure plants into the soil
Give yourself plenty of time in deciding when to dig the green manure plants in. However, also take into consideration the time it will take for the green manure plants to begin to decompose. You don’t want to be planting vegetable seedlings into ground that has just had green manure plants turned in, as the decomposition stage will generate heat, which could damage your delicate seedlings.
Try to allow at least 2-3 weeks before planting or sowing seeds to the prepared ground. Watering the ground during warm spells will help speed up the decomposition of the green manure plants.