Sow now to make the most of catch crops

BETWEEN now and September 15 farmers will sow 20,000ha of catch crops and 10,000ha of oilseed rape. The increase in the area of catch crops has largely been driven by GLAS and to a small extent by farmers who are sowing catch crops in order to comply with ‘greening’ for the basic payment scheme. Catch crops for both GLAS and ‘greening’ must be sown by September 15.

However, to achieve the real benefits all catch crops should be sown as soon as possible. A day in July is worth one week in August and the month of September.

Sowing by the last day specified by a scheme will enable scheme payment, but both the benefits to land and the potential for grazing are lost if you delay too long.

If you fail to get benefit from the land or to graze the crop, the entire financial benefit of the schemes will be lost to you as the cost of establishing catch crops is equal to, if not greater than the GLAS payments.

There is no point in turning money — you need to keep some. ÷The major benefits to land from sowing catch crops are: improvements to soil structure promoted by the addition of organic matter to soil; ÷Reduction in leaching and soil erosion, which has become an increased concern in recent years with more intense rainfall events; ÷Improved soil aeration from plants with tap roots, fixation of nitrogen with legumes.

While the benefits, if the crops are well established, can be substantial, there are also a number of serious concerns.

The biggest issue in my opinion is that we are sowing too many brassicas — forage rape, leafy turnip and mustard.

These host diseases which affect oilseed rape, our major alternative crop.

Currently we grow approximately 280,000ha of cereals and 40,000ha of break crops comprising of beans, peas, oilseed rape and potatoes.

That gives us only 12.5pc of our tillage land under a break crop — our target for a viable tillage business is 25pc (similar to what is being achieved in the tillage areas of most European countries).

All of our break crops have management issues.

Beans need moisture retentive soils and harvest is late to very late.

Peas are for specialist growers on suitable land and subject to high losses given wet weather at harvest.

Potatoes need huge capital investment and price is subject to collapse with oversupply of either home grown or imported potatoes.

Oilseed rape, which needs good moisture, retentive soils and good rotation, has the best potential for expansion and for achieving our 25pc target despite the risk of shedding at harvest. However, it can normally be well managed with the use of pod sealants and the introduction of new varieties with resistance to pod shatter.

Is there a danger that the increase in brassica catch crops will restrict the expansion of oilseed rape?

My next major concern is that late sowing of catch crops will result in poor germination in the autumn and leave viable seed for germination the following spring when they will become a ‘weed’ in the newly sown crop.

The biggest problem in getting catch crops established on time is workload.

They must be sown in July or August with the best opportunity presented by an early harvest of winter barley and an interval before spring barley harvest is commenced.

That opportunity is there this year. A short interval between harvesting winter barley and clearing straw is largely what has limited oilseed rape area in the past as farmers are well aware that late sowing gives poor yield.

Whatever hope you have of establishing a good catch crop with sowing up to mid September, this is virtually eliminated with the GLAS requirement of establishment without ploughing. Therefore, in the interests of your own land, make every effort to sow your catch crops as soon as possible.

The Department of Agriculture expect to have the recommended list for oilseed rape early this week.

It is likely to list Anastasia, a conventional variety from Seedtech which is the highest yielding variety on the AHDB recommended list for the North Region but is not listed on the East/West Region.

It is suitable for later drilling and has good standing ability. PX 113 is a semi dwarf variety which is lower yielding, but is easier to manage at harvest and perhaps the ideal variety for new growers. It has good resistance to light leaf spot and resistance to stem canker.

Extrovert is a hybrid variety from Goldcrop which is likely to be the highest yielding on the list.

It has good resistance to light leaf spot, is vigorous and will require management for growth regulation.

SY Harness (Goldcrop) is a hybrid variety rated 108 in the AHDB North Region and 104 in the East West Region, with good vigour that will require management. If sowing late (early September) good plant vigour is critical.