You will need to try and keep control of it by constantly taking off straying branches while it is easily done. Especially if near a boundary. Laburnums drop petals and then long seed cases then leaves and can annoy neighbours. Our one is dangling over our back neighbour who used to cut it his side, and we took it back over our side, amicably. Now its rented not so easy. So yes you can cut it is the shorter answer.