We have two drainage ditches that run from above down through our big garden, though as a result of years of neglect the ditches are now looking considerably more like natural drainages: intermittent streams of variable depth and width, with their banks firmed up by shrubs and young trees we planted along them. The first drainage ditch continues down into woods below our property. At the bottom of this ditch years ago I planted old roses, which have thrived with all the water and nutrients. Below that, on the neighbors property, is a jungle of bramble and nettles backed by elms. I used to keep the ditch clear, because that's what you're supposed to do, right? One day it occurred to me how extraordinarily rich the nettle- and bramble-infested ground below the garden was, with beautiful light soil: that was because the turbid water ran down through the clear functional ditches, hit the weeds, and dropped its load of sediment. Hmmmm, I said. I decided to begin blocking the ditch at the bottom of our property. The ground around the ditch drops there, forming a kind of hollow. I filled the drainage with pruned organic debris of all kinds, thinking to slow the water there and capture the sediment. This has been working, slowly. Last night we had a vigorous rain, and when I went to check the ditch, a good deal of sediment had in fact been captured overnight, and the water was flooding to the low ground on the sides, leaving sediment there, too. I may be drowning my roses, that's my only concern. It could be I'm making a memorable mistake, but the roses are just beginning to leaf out, and I've had experience of roses living through prolonged flooding while dormant and not being bothered by it. And I think the water will diminish fairly quickly. So I'm letting the current state of affairs continue.