Green manure crops are a valuable addition to any garden, providing numerous benefits to the soil and overall plant health. Planting these crops at the right time and using the correct techniques is crucial for their success. In this article, we will explore the best time to plant green manure crops and discuss the techniques to ensure optimal growth and fertility.
The Best Time to Plant Green Manure Crops
Green manure crops are typically sown either in the fall or spring, depending on the specific crop and the region’s climate. Let’s take a closer look at each season’s ideal planting time.
Fall Planting
Fall is an excellent season to plant green manure crops, as they can help prepare the soil for a lush spring garden. The timing of the fall planting will depend on the previous summer crops’ harvest:
- In late summer (mid-August to September), consider sowing leguminous crops such as lupine, melilot, sainfoin, alfalfa, or clovers.
- In the fall (mid-September to late October), opt for a mix of legumes (winter peas, fava beans) and grasses (oats and wheat or rye).
Early fall plantings give you the opportunity, especially in mild climates, to start new crops like peas, shallots, or onions as soon as the green manure crops are destroyed.
Spring Planting
The spring season, typically starting from early to late March depending on the region, is another suitable time to sow green manure crops. This planting will prepare the soil for the summer garden. Some common green manure crop options for spring include phacelia, white mustard, camelina, fava beans, blue flax, buckwheat, sainfoin, alfalfa, melilot, clovers, winter peas, or a mix of oats and peas. The green manure should be cut and mulched within one and a half to two months after planting, before it goes to seed and after the last frosts in May. After a waiting period of three to four weeks, you can then plant your summer vegetables.
It’s worth mentioning that green manure crops can be planted year-round, especially if you have protected growing areas or live in regions with mild climates. In such cases, opt for a mix of species that have a short vegetative cycle and include leguminous varieties.
Techniques for Planting Green Manure Crops
Green manure crops are generally easy to grow, requiring minimal maintenance and resources. To ensure successful growth, follow these essential techniques:
- Prepare the soil by removing stones, weeds, and their roots. Break up any clumps with a garden fork and level the surface using a rake, as you would before planting flowers.
- Sow the seeds evenly across the prepared area. The recommended seeding rate varies depending on the specific crop, so refer to the instructions on the seed packet. For example, you may need to sow 100 to 200 grams of fava bean seeds for every 10 square meters, while only 15 grams of mustard or phacelia seeds would suffice for the same area.
- Press the seeds into the soil by gently tamping the surface with the back of the rake or using a lawn roller for larger areas. Some crops like buckwheat or sorghum may require slightly deeper burial, in which case, perform a line sowing with a maximum spacing of 10cm between rows.
- Water immediately after sowing, preferably using a fine rose on a watering can or a gentle spray setting on a hose nozzle. This will help the small seeds adhere to the soil and promote quick germination. Keep the soil moist until the seedlings emerge.
- Allow nature to take its course with rainfall, as the green manure crops will grow once they reach a height of around 10cm. If rains are delayed, it’s advisable to provide supplemental watering until the seedlings reach this stage.
Once the green manure crops have developed their floral buds, it’s time to cut them down to prevent seed formation and unwanted spontaneous growth.
