Best management practices to alleviate deep-seated compaction in asparagus (Asparagus officinalis) interrows (UK)

Field operations associated with UK asparagus production (re-ridging and intensive foot and vehicular trafficking of the wheelings) can result in severe deep-seated compaction in interrows, impacting on crop health and productivity. In this project, we investigate the long-term efficacy of a range of Best Management Practices (BMPs) targeted at preventing or remediating soil compaction in asparagus (Asparagus officinalis L.) interrows as compared to Conventional practice. BMPs included (1) companion crops - Rye (Sereale cecale L.), Mustard (Sinapis alba L.), (2) interrow surface mulch applications (straw mulch and PAS 100 compost in combination with shallow soil disturbance (SSD)), (3) modifications of the conventional tillage practice (re-ridging (R) or not ridging (NR) and applying SSD or not applying SSD) and (4) a zero-tillage option. In general, companion cropping had no effect on soil compaction or water infiltration rates as compared to the Conventional practice. Application and incorporation of straw mulch or PAS 100 compost however significantly reduced soil compaction of the interrows to >0.45 m beyond the working depth of the subsoiler (0.25 m). Composts and mulches in combination with SSD significantly reduce deep-seated compaction of the interrows within 3 years of annual application. Further, Conventional practice equivalent treatment (Bare soil No-SSD R) was associated with significantly higher PR values as compared to the zero-tillage (Bare soil No-SSD NR). These findings show that the extremely high levels of deep-seated compaction in interrows, associated with re-ridging, foot and vehicular traffic can be alleviated using surface mulches in combination with SSD.