Sowing technology for catch crops

Tine seed drill? Coverseeder? ‘Geohobel?’
Establishing catch crops is becoming more and more difficult with increasing drought. What role do different sowing techniques play in this? We have tried it out. The comparison of different sowing techniques for catch crops was on display at the well-attended field day at Peter Arndt’s Hof Capelle. The advantages and disadvantages of the sowing techniques used were illustrated by means of the demo field and initial results from analysing the growth.

The demo field

Immediately after the wheat harvest (14 August 2023), demo strips of the catch crop MaisPro TR (DSV TerraLife organic) were sown with these sowing machines:

• Farm variant:
  • Zinkendrille (Kuhn Megant) (Tine seed drill) + double tillage (stubble cultivation with cultivator – second tillage with cultivator before sowing) – sowing on 28/08/2023

• Tine seed drill variant:
  • Tine seed drill (Kuhn Megant) + single tillage (stubble cultivation with cultivator) – sowing on 15/08/2023

• Coverseeder variant:
  • Coverseeder (Müthing) – without prior tillage – sowing on 15/08/2023

• Geohobel variant:
  • Geohobel (Rath) – without prior tillage – sowing on 15/08/2023

The Coverseeder can sow in crop residues and cover the seed in a single work step without prior tillage. Organic material is not worked into the soil. The Geohobel works with a special planing knife that shreds and mixes 3 – 5 cm of topsoil including stubble. Both devices create a mulch layer that helps to regulate the hydrological balance and prevent erosion. This is particularly important when the catch crop seed is threatened by persistent drought. Both techniques also promise to regulate weeds and volunteer cereals. The variant usually used on the farm uses the Tine seed drill as a sowing technique. This is preceded by two tillage passes with the cultivator. Which variant performed best on our demo field? To find out, four 50cm² biomass sections were cut on 5 October 2023 and the dry matter of the growth per species was determined for all variants.

In both sowing variants without prior tillage (Coverseeder and Geohobel), the proportion of volunteer cereals (wheat) was highest. A significantly lower proportion of weeds and volunteer cereals was found in the variant usually used on the farm with two tillage operations. Direct sowing without prior tillage can be particularly advantageous when the residual moisture in the crop is to be optimally utilised. As the precipitation levels on site were sufficient for the establishment of the intercrop in the trial year 2023, the potential of this technique could not be sufficiently evaluated in this year.