Miscanthus Giganteus: a developing perennial crop.

Miscanthus Giganteus, nicknamed “elephant grass”, is a perennial grass. Native to Asia, this plant adapts perfectly to European climates. Today, it is cultivated for use in biomass energy, biomaterials and agricultural and horticultural mulching. Its rapid growth and extensive root system enable it to store up to 10 times more carbon than permanent grassland.

When to plant miscanthus?

Planting miscanthus between April and May gave the best results in terms of recovery rate and quality. This planting window ensures optimal germination and growth, essential for high yields.

Soil preparation

Soil preparation is a key step: a poor texture or an unsuitable working depth could considerably reduce the rate and quality of Miscanthus rhizome recovery. Miscanthus cultivation requires a fine texture, similar to a preparation for potatoes or wheat seedlings, to a depth of 15-20cm.
Depending on your soil type, rotovator or rotary harrow will be needed to increase soil macro-porosity and allow root development. This preparation facilitates rhizome planting and encourages uniform growth, a sine qua non for a successful harvest.

What planting density?

Mechanized planting of Miscanthus requires suitable equipment. Rhizomes must be planted to a depth of 5-8 cm. Mechanized planters guarantee fast, uniform planting, suitable for large-scale farms.

Miscanthus in figures

• 0.5 to 1m2 = 1 rhizome or seedling
• 0.80m = space between 2 plants
• 3 or 4 = maximum number of rows for 5m width
• 500plants=4 rangéesde100m=1aum2

You’ll find miscanthus rhizomes ready to plant, with health guarantees, delivered in bags or BigBags, with quantity discounts here

What are the diseases and pests of Miscanthus?

Diseases: No diseases have been identified on miscanthus in Europe. We will inform our customers in the future if any diseases appear.

Pests :

Wireworms can cause considerable damage, especially if miscanthus is planted just after fallow land or permanent grassland. So it’s best to sow an annual crop between the two to break the wireworm cycle.

Wireworms can cause serious damage when miscanthus is planted after a period of fallow or permanent grassland. To prevent such damage, we recommend planting an annual crop in between to break the wireworm cycle. An anti-mole treatment can be applied before planting.

Rabbits can also cause damage during the first few months if they are numerous. In this case, temporary protection should be installed, but we have had very few reports of rabbit damage.

Miscanthus technical itinerary

Miscanthus cultivation requires very little intervention, which is its main agronomic advantage. However, rigorous weed management is essential in the first year.
Several combined weed control methods can be used, depending on pressure, available equipment and soil type:

False seeding :

After ploughing, the false seeding process consists in stimulating germination of the seeds present in the seedbed. The soil is worked on the surface, using the seeding tool, but without seeding. You need to wait a fortnight for the weeds to germinate.

These weeds are then eliminated by a second superficial pass of the tool, this time coupled with the act of seeding.

Application of the false seedling method requires prior planning of soil preparation.

It is advisable not to use false seeding in the following situations:

• Clay soil liable to form compact agglomerates.
• Silty soil with a strong tendency to compact.
• Late soil preparation.

Weeder

The currycomb harrow eliminates weeds at the seedling stage, so you need to intervene as soon as you sow and then at each emergence, weather permitting.

Just before the miscanthus emerges, the currycomb harrow makes its first pass, with the tines set to a low-aggression position, to work superficially (1 to 3 cm). This is known as “blind passage”. Weeds must have germinated.
Be careful to pass early enough not to reach the miscanthus germ, which is very fragile. The later you sow, the less time you have for intervention.

Hoeing

From 3-4 leaves, the weeder takes over from the curry harrow.

The working width of the weeder must be identical to that of the planter.

This hoeing may enable weeds that have resisted the previous harrowing to be pulled out
Hoeing, like harrowing, must be followed by a few hours without rain to prevent transplanting.

When hoeing, you can also do some ridging. This involves covering weeds in the row with a sufficiently developed miscanthus, using discs, ridging shares or a star weeder.

Herbicides

In the event of extreme pressure and planting under difficult, non-ideal conditions (planting too early, poor rhizome recovery rate, etc.), a selective post-emergence herbicide may be applied. Nevertheless, Miscanthus forms a dense plant cover from the second year onwards, preventing weeds from breaking dormancy.

Fertilization

Miscanthus requires very little fertilization, and is often considered “self-fertilizing”.

1. Nutrients and exports
   • Some of the leaves fall in autumn, providing a mulch which, when slowly decomposed, will increase the soil’s organic matter content (approx. 0.1 to 0.3% per year), and hence its fertility.
   • During the senescence phase in autumn, some of the nutrients migrate from the aerial parts to the rhizomes, replenishing their reserves.
   • Annual exports amount to some:
     • 50 to 80 kg of nitrogen per year.
     • 5 to 10 kg of phosphorus per year.
     • 70 to 120 kg of potassium per year.
2. Nitrogen inputs:
   • Nitrogen application does not increase Miscanthus productivity and is generally not recommended, as it favors weed development and can lead to lodging (stem collapse) during the senescence phase.
3. Phosphorus and Potash Control and Input:
   • For phosphorus and potash, it is recommended to carry out control analyses after 5 to 10 years. This makes it possible to assess the specific needs of the plot and determine whether additional inputs are required.

Miscanthus harvest

• Miscanthus is generally harvested dry, at the end of winter, typically between February and the end of April, depending on weather conditions.
• Miscanthus stalks, similar to fine bamboo canes, are harvested when their dry matter content exceeds 80%. Depending on weather conditions, this level may not be reached until spring.
• Harvesting is generally carried out with a forage harvester fitted with a Kemper spout + a tractor-bin combination, or a combination of mowing and baling with a high-density baler.
• Strand size must be adapted to the type of packaging. For bulk harvesting, short strands are preferable, whereas baling requires longer strands (100 mm minimum).
• Miscanthus straw has a low density: around 100 kg/m3 in bulk and up to 250 kg/m3 in bales, which greatly limits its transport over long distances (over 40 km for bulk in particular).

Miscanthus storage

miscanthus does not need to be dried, and can be stored in bundles or in bulk, under a shed or in a covered silo. However, as miscanthus chips are not very dense, a large storage area is required: around 40 m2 by 3 to 4 m high to store a hectare’s harvest.