More than 77,000 bales of wheaten straw will have to be imported in the coming year to make compost for mushroom production. This is about 43% of the 177,000 bales used annually by the sector.

The figures were outlined to growers in recent days by the two firms which make mushroom compost – Walsh Mushrooms and Monaghan Mushrooms.

The former has announced a €25/t price increase for its compost, bringing its price for the next 12 months to about €230/t.

It has told growers the price increase is due to an increase in demand for for wheaten straw this autumn and because of the need to import further supplies of straw. Wheaten straw is available in the UK and France but transport costs are significant.

Compost accounts for 37% of a grower’s cost of production. A typical grower buys 50t per week at a cost of €11,500. The increase in compost price increases a grower’s cost of production by 5%. Compost prices for growers in Holland, Poland and other countries can be €50/t lower than here.

IFA mushroom chair Gerard Reilly said growers were very concerned at the price increase: “€230/t is the highest price that I have ever been asked to pay for compost.” He said growers who supply the Irish market through producer organisation CMP have this week notified retailers of a price increase. “We had no choice but we have got a good response from retailers.”

Nonetheless, the big challenge for Irish growers will be the UK market, where 90% of their production goes.

Chief executive of producer organisation CMP Donal McCarthy warned that growers will have to obtain higher prices from the UK to remain in business.