Catch Crops, Cover Crops and Green Manures are terms generally used to describe a crop that is sown between two cash crops. Broadly speaking they all help to improve soil structure, increase organic matter content and help with trafficability, but there are some key functional differences between each type of crop;

• Catch Crops capture excess nutrients leftover from the previous crop preventing nutrient leaching.
• Cover Crops cover the ground to reduce soil erosion and weed build-up.
• Green Manures provide nutrients for the following crop.

Having an actively growing crop in the ground over winter has several benefits over leaving ground fallow.

• Firstly, these crops provide ground cover which prevents soil erosion and suppresses weeds.
• The varying root structure of catch crop mixtures helps to improve soil structure which influences nutrient release, water retention and makes land more trafficable.
• Catch crops can enhance soil chemical and biological characteristics.
• Catch crops can retain and release nutrients for the following cash crop.
• Depending on the species used, catch crops can break pest and disease cycles.
• Some catch crops can be grazed by livestock over winter.
• Sowing catch crops is supported by DAFM schemes like ACRES.

What Catch Crops Should I Sow?

There is a wide range of species to choose from that will perform one or more of the
functions above, but they are usually sown in mixtures to maximise the benefits of sowing.
In Ireland there are 3 groups of plant species typically used in Catch Crop mixtures

1. Brassicas: typically used for soil conditioning, nutrient capture and as winter feed.
They have rapid autumn growth, provide good ground cover, are deep rooting and
suitable for late summer/early autumn sowing. Not to be used before or after
brassicas in rotation. Common species include mustard, tillage raddish, leafy turnip
and forage rape.

2. Legumes: primary function is to fix N for following crop and offset inorganic N
requirement. Legumes tend to be deep-rooting and can also improve soil structure.
Should ideally be sown in summer and can be slow to establish later in autumn.
Rates of N fixation will be lower in winter. Common species include red clover, vetch
and crimson clover.

3. Some alternative species that may be useful cover crops. Many of these species are
not related to commercial crops grown in Ireland and therefore are ideal in rotation to
break pest and disease cycles. Species include forage rye, Westerwold ryegrass,
buckwheat and phacelia.

Choose a species or mixture based on your rotation and soil requirements e.g brassica
species are not suitable where oilseed rape is in the rotation.

The success or failure of Catch Crops is largely based on sowing date and good
establishment. Drilling as soon after harvest as possible will give your Catch Crop the best
chance of establishment. No ploughing is needed for establishment and seed can be drilled
or broadcast.

DLF Catch Crop Range