I have two raised beds, one is brick with crumbling mortar, the other is knackered concrete. They have each seen much, much better days. They are sloping, and the very top of the bottom walls (which basically support it all) is crumbling. This isn't helped by my young DS picking whatever pieces of concrete or brick or mortar off that has crumbled and dropping it on the ground (he has ASD). As a result, when I am watering the beds, the soil is running downhill and falling to the ground and I am losing soil every time I water. I am using the sprinkler setting on the hose so that there isn't a whoosh of water, but I am still losing soil. The beds are about 10 metres each wide x 2-3 metres deep. There are some curved edges, they are not completely rectangular with 90 degree corners. I have shrubs and perennials in them.
Can anyone suggest what I can do to improve the situation please? I am a novice gardener so don't have any ideas beyond this decorative edging.