gravel mulch

From working in the garden the other day, I’ve come to the conclusion that gravel does not make a good mulch for much of my garden. Let me first say that it IS good for the penstemon and other native plants which self-seed readily in the gravel. It does reflect some light and heat from the soil, and moderate temperatures below ground. It does help retain some moisture in the soil. It does have a nice finished appearance. For those reasons, I will still use it in the less worked areas of the garden.

But for those areas of the garden where things change every year, it isn’t such a good mulch. It is hard to clear away from the soil - when raking the mulch away from an area to plant, there is always some gravel left, and unless I spend a lot of very tedious time picking out every bit of gravel, that gravel gets incorporated into the soil. Over time, since I tend to move plants a lot (re-designing, re-planting, and trialling plants), all the gravel will be dug into the soil. I don’t really want to garden in a gravel pit, but perhaps I’m too concerned about the small amount of gravel it really is. It’s much easier to rake away an organic mulch, and any organic material that’s dug into the soil will decompose and be beneficial.

The gravel also collects blown sand and dust, and in this climate, with the wind storms, the gravel soon fills in. Unless I want to spend a few weeks every few years sifting the gravel, I’ll soon lose the gravel mulched appearance.

Is using gravel as mulch a sustainable practice? I think not. From what I’ve read, it isn’t.

When watering by hand, it’s hard to tell if the water is soaking in to where the roots are, since the water can just run under the gravel on the surface of the dry soil and spread out, or it can come out somewhere downhill.

So in some areas of the garden, where I move plants around a lot, I wish I hadn’t put in a gravel mulch. A pecan shell mulch would have been better. Live and learn.