First, ask your accountant. It's impossible to advise meaningfully without knowing your own and your company's situation and prospects.
Some of the wiser heads among the farm tax advisory community suggest that incorporation is only suitable for a small minority of ultra-profitable farm enterprises, which would I expect rule out almost all part time farm. Besides as farm subsidies are paid only to individuals and not to incorporated bodies even where an incorporated body carries on the farm trade, you would remain subject to income tax, PRSI and USC on this element of the farm earnings, which might well negate the tax savings you would otherwise expect to achieve from incorporation.