Bedding Rock and Gravel

Rock does not break down, does not blow away, and does not need replacing every year.  That makes it the sensible choice in the places where organic mulch keeps disappearing: drip lines, slopes, drainage runs and high-traffic edges.

The trade-off is that stone contributes nothing to the soil.  Organic mulch breaks down into the bed and improves it over time; rock sits on top and stays there.  In a bed full of shrubs and perennials that soil contribution is worth having, which is why rock is usually the better answer in structural and functional positions rather than in heavily planted ornamental beds.

It is also a decision that is expensive to reverse.  Taking a rock bed back to mulch means removing every stone, which is considerably more work than the reverse.  Worth being sure before it goes down, and worth reading the mulch and pine straw page alongside this one.

Fabric under stone slows weeds coming up from the soil below.  It does nothing about the ones that arrive from above, and over time that is where most of them come from.

Dust, leaf litter and organic debris collect in the gaps between stones and gradually build a thin layer of soil on top of the fabric.  Seed lands in that layer and germinates in it, entirely above the barrier that was supposed to stop it.  That is why a rock bed which was clean for two years starts producing weeds in the third.

Fabric also complicates the bed later.  Roots grow into it, it tears when the stone is moved, and pulling degraded fabric out from under an established bed is unpleasant work.  It has a place, but it is one component of keeping a bed clean rather than the answer to it.

The practical maintenance is periodic: clearing the debris out before it becomes soil, and treating what does come through.  That is far less work than letting it establish.

A stone bed does not need topping up every year the way mulch does, and that is a real saving.  It still needs clearing out, weeding and occasionally topping back up where material has moved or sunk.

Leaves and needles have to come out, because leaf litter left in stone is exactly what turns into the soil layer that weeds grow in.  Clearing a rock bed takes a lighter touch than clearing a mulched one, since the object is to move the debris without moving the stone.

Over several years stone also settles into the ground beneath it and thins out at the edges.  Topping up is occasional rather than annual, and it is a smaller job than an annual re-mulch, which is generally the point of choosing rock in the first place.  Bed edges and the planting inside them are looked after under flower bed maintenance.