So the story .... put down need flower beds, finished off with Mylex and bark laid on top. Every morning I come out the bark is scattered over garden, I assume this is a cat, scattering it around.
Far more likely to be birds tossing it around looking for slugs, woodlice etc. sheltering underneath it. Cats have far better things to be doing with their time
the 'mypex' should not really need to be used in theory. The point where one of the factors required for the growth of any plant - in this case light is eliminated - is achieved by the bark.
The bark need to be able to 'stick' to something ie. moisture and it cannot achieve this on a plastic underlay.
It would also appear that you maybe using a large chip mulch which will frixxle/ dry out in this summer sun.
Try for the fine mulch and eliminate the mypex[the semi permiable membrane] this will - at the right depth - sort out your problems. If the bark breaks down ie. turns from muclch to compost the weeds will germinate on top. Spot spary with a translocated herbicide to solve this.
Skutch grass or it scutch grass . No matter how much we try to remove it by pulling it out at the roots we are losing the battle. We can tolerate it in the grass if we have to. but the flower and shrub beds don't appreciate it. Would the bark do the trick!!!!