It depends on which model it is - as a guess, you would need something that can tow a minimum of 2500 kg (approx 1000kg trailer, and 2 x 500kg for the horses).
Here are the towing weights for a Cherokee http://www.cuddles.abelgratis.net/jeep.htm
I have towed with my Cherokee 2.5ltr petrol sport for 5 years. It tows very very well. Never had any issue towing with it including 2 trips from northampton to manchester.
Also great car when not towing.
Hi .... I think the cherokee is fantastic to tow with, I drive a 2.5TD , although hubbie tows he has said its far better than the disco, there is plenty of power behind them . its not dead like the disco either sorry all disco owners ... (we did have one but no get and go in it )