TerraLife® Cultivation Recommendations

Information

Growing TerraLife® Mixtures Correctly

A good cover crop makes a significant contribution to soil regeneration between two main crops. The better a catch crop develops, the more it promotes formation of soil organic matter, nutrient retention and nutrient dynamics. It is therefore important to plan the sowing of the catch crop carefully. When subsequently assessing the catch crop, it is not just the above-ground biomass that is decisive. The influence of the roots on soil biota activity, soil structure and soil organic matter is a key assessment criterion.

This is precisely where TerraLife® catch crop mixtures come into their own. Thanks to their diverse, well-balanced species composition, they create a heterogeneous, extensive root system. This penetrates the soil at various depths and with varying intensity. In this way, nutrient reserves are tapped into and mobilised in many places. At the same time, this improves the soil’s structure and pore volume. Root exudates bind and stabilise soil aggregates, forming water-resistant crumb structures. This protects against compaction and silting. Furthermore, pore channels are created and stabilised, thereby promoting the soil’s air and water balance. Overall, a mixture acts as a kind of ‘insurance’. The interaction of different species ensures the success of the catch crop, even under dry conditions, for example.

Nevertheless, once the mixture has been selected, optimal sowing conditions must be created for successful catch-crop cultivation, considering crop rotation, sowing date, sowing technique and intended use.

To save water and prevent competition from volunteer cereals or rapeseed and other weeds or grasses, sowing should take place immediately after combine harvesting using shallow tillage implements.

In dry years, this is particularly desirable to minimise evaporation. Multiple soil tillage operations always result in a loss of usable water. If, due to weather conditions or for reasons of labour efficiency, it is not possible to sow the catch crop shortly after the harvest of the previous crop, volunteer cereals that have emerged must be controlled using appropriate soil tillage measures.

In this regard, particular attention should be paid to the swath area once the straw has been harvested. In some cases, additional control of volunteer cereals may be required here. Sowing times should be adapted to regional conditions. Most TerraLife® mixtures benefit from sowing between mid-July and mid-August. At this time of year, the soil is usually warm and the length of daylight is ideal. Selected late-sowing mixtures such as TerraLife®-VitaMaxx DT or TerraLife®-CoolSeason can also be sown in September, depending on the location, and are not suitable for early sowing dates.

Even before the previous crop is harvested, there are several factors to consider regarding the establishment of catch crops.

Depending on the previous crop, organic matter of varying types, quantities and spatial distribution remains on the field. This can affect the establishment of the catch crop in different ways. In the case of previous grain crops, for example, the straw can be cleared away or left on the field. To ensure reliable emergence of the catch crop, various factors must be considered:

  • Fine chopping of plant and straw residues reduces mechanical resistance to the catch crop seedlings.
  • A uniform distribution of crop residues promotes even emergence across the field.
  • The type and quantity of crop residues influence the sowing technique. For example, a layer of straw that is too thick can block the seed drill.
  • The type and quantity of crop residues determine the nutrient dynamics in the soil. For example, cereal straw has a very high C/N ratio, which means that, once incorporated into the soil, the availability of nitrogen for the catch crop may be significantly reduced.
  • When managing crop residues prior to establishing the catch crop, the site-specific soil conditions and current weather conditions must always be considered.
  • Covering the soil surface with crop residues protects against water evaporation, silting and erosion.

Furthermore, the lodging and volunteer growth behaviour of the previous crop determines seedbed preparation and the choice of catch crop. Barley (Hordeum vulgare) and rye (Secale cereale) can volunteer in catch crop stands. Consequently, in such crop rotations, it is important to adapt tillage practices and select highly competitive catch crops that establish quickly and deprive the volunteer cereals of light, water and nutrients.

All TerraLife® mixtures contain smaller and larger seeds; therefore, the optimum sowing depth is a maximum of 2 to 3 cm. When preparing the seedbed, particular attention must be paid to the requirements of fine-seeded crops, which need a fine, crumbly seedbed that has been well compacted. Generally, care must be taken to ensure that straw is distributed evenly beforehand.

There are various approaches to sowing a TerraLife® catch crop mixture. The farm’s technical equipment largely determines the sowing technique used. However, the success of a catch crop is very much dependent on its successful establishment. Simply broadcasting the seed carries a significantly higher risk, as most species require soil cover. When using a broadcast sowing method, higher seed rates should be allowed for, and conditions (e.g. weather) should be ideal.

A catch crop mixture can be sown using a drill after tillage has been carried out, or by direct drilling into the stubble on the day of threshing following previous crops such as rye or wheat. The use of rollers in conjunction with broadcast or drill-sowing techniques can also be effective and efficient. The key factors are an even, shallow seed placement with sufficient reconsolidation.

The straw must be distributed evenly; it may be necessary to use a straw harrow and/or to mulch the stubble. As nitrogen mineralisation in the topsoil is minimal under dry conditions, it is advisable to apply nitrogen when direct drilling.

The sowing rates for TerraLife® mixtures are calculated to ensure an optimal seedbed and optimal sowing times and must be strictly adhered to due to the varying competitive behaviour of the individual components in the mixture. The sowing rates should only be increased in the event of unfavourable conditions or broadcast sowing, such as inadequate seedbed preparation or delayed sowing.

TerraLife® mixtures can benefit from moderate initial fertilisation. This depends on the C/N ratio of the cover crop itself, but also of plant residues from previous crops. 

Attention must be paid to the legal framework in the relevant region. In some areas, fertilisation of cover crops is limited to a specific amount of nitrogen or is entirely permitted. 

To offer a wide range of solutions, DSV offers its most famous mixtures with different legume shares. Therefore, the mixtures TerraLife®-MaizePro DT 50, BetaMaxx 50 and N-Fixx 50 contain less than 50 % legumes. TerraLife®-MaizePro DT 30, BetaMaxx 30 and N-Fixx 30 contain less than 30 % legumes. These limits in legume share determine, for example in Germany, if and how intensively a cover crop can be fertilised. 

It is desirable to achieve a long period of ground cover using a TerraLife® mixture. This allows photosynthesis to continue for as long as possible. However, there are reasons to interrupt growth. Should individual species, e.g. buckwheat, white mustard, oil radish or phacelia progress from the flowering stage to seed formation during mild autumn days, it is advisable to reduce the cover crop. In such cases, it is recommended to halt growth in good time to prevent the seeds from ripening.

If complete reduction is desired during the winter and weather conditions (frost) cannot be reliably predicted, it is advisable to carry out a rolling or crushing operation at the end of the growing season, preferably at the first frost, to ensure thorough freezing and even incorporation in the spring. Generally, the vegetation should not be incorporated whilst still green in late autumn.

TerraLife®-MaizePro DT, MaizePro DT 30 or 50. TerraLife®-CoolSeason and mixtures containing TerraLife®-SoilProtect are winter hardy or partially winter hardy. The aim here is for certain species (e.g. winter vetch, crimson clover) to persist throughout the winter and form a ‘green bridge’ to the next main crop. These are incorporated into the soil during seedbed preparation in spring.

General notes

It is essential to follow the instructions for the use of herbicides in the previous crop

  • If sowing takes place too early or under stressful conditions (particularly drought stress), some plant species (buckwheat, white mustard, oil radish, phacelia) may set seed prematurely. In such cases, it is advisable to halt growth in good time to prevent potential seed ripening (if used as a cover crop, observe greening requirements)
  • As a general rule, the cover crop should not be incorporated whilst still green in late autumn
  • If the mixtures are left in place over winter, it is advisable to roll or crush them at the end of the growing season to ensure they freeze through and can be incorporated evenly in the spring (exceptions: MaisPro DT, Landsberger Gemenge, CoolSeason and FutterGreen)
  • Other suitable sowing methods include slurry sowing and combine sowing (optionally followed by rolling)