No experience here, but reading it makes me want to go right out there and pull back the gravel in the front yard and see what it's like under there, but I'll wait until later this evening when it's cooler.

This is first of the posts about gravel for mulch (that I found anyway) which was about half way down on the Cottage Garden thread titled "No Wonder":

RE: No Wonder!
Posted by wonbyherwits z7b NC (My Page) on Thu, Jul 28, 11 at 21:15

It is bad news, isn't it? Weather extremes everywhere. It was still 99 degrees at 7:30 pm tonight, but I had to water the garden...and, I started feeling guilty about watering FLOWERS! Although my flower garden has brought great pleasure to me, it is for the pollinators and birds now that I make efforts to keep it alive. I'm even feeling sorry for the deer and rabbits.
We've had our a/c on 77 inside and sitting under a ceiling fan and it isn't that bad when you walk in from 102 outside (heat index 110). It may hit 105 here tomorrow.

Now... this is surprising to me.... bear with me.... long story.

Back in the spring, we converted several garden beds that had been mulched with compost and hardwood into one continuous gravel garden with our guest parking (story link below).

Anyway --- we've had a summer of 90+ 100+ temps, very little rain for weeks at a time, then nothing that soaks in.

In the gravel garden, there are buddleia, rosemary, hollies (2 kinds), crepe myrtles, Japanese iris, bee balm, yucca, osmanthus goshiki and chamaecyparis. This entire summer -- I HAVE NEVER WATERED ANYTHING IN THE GRAVEL GARDEN!

Out of curiosity, I pushed some gravel aside and the soil was moist and I dug down probably 10 inches. Those plants that are mulched with gravel area doing better than anything else growing here. It is a southwest exposure, but the sun doesn't really hit it hard until 11:00 am.

What surprised me most was the bee balm and Japanese irises. The foliage looks better on those than comparable plants other parts of my garden. I really thought those plants would die from the reflective sun, but I didn't want to move them when we put down the gravel. Now, I'm glad that I left them alone.

The moisture isn't evaporating from the soil beneath the gravel. Now, that makes me wonder what will happen in the winter when we should get a lot of rain. The soil drains well under there (in the past), so I hope all will be okay next spring.

I'm moving cautiously about changing other areas, but I have plants that I think can take it.

I used to think that gravel was just for agave, yucca and such. I never had thought about using it for other plants. I grow agastache, salvia, russian sage, coreopsis and other drought-tolerant plants that just might be better off mulched with gravel.

Unlike hardwood mulch, gravel is a pretty serious move... not easily undone! We're going to experiment a bit more with this technique to see the results.

Has anyone else done this? I've seen so many European gardens done this way, but their latitudes are much cooler than here. I've seen southwest gardens done this way for Mediterranean plants. I've seen scree gardens here, but I've never seen what we've done used around North Carolina.

Cameron

Here is a link that might be useful: Cameron linked this article ...

Well, the black clay ground was dry as a bone under an area of thick gravel in my yard; and this is after almost an inch of rain a week or two ago.

But speaking of gravel I've used lava rock as mulch in a couple of places under shrubs and in some pots, expecially in the pots of bougainvilleas. It keeps soil from spashing out when they are watered. I also use it in pots planted with agaves and cacti whose soil does not need replenishing. It also keep the squirrels from digging in the pots. For roses in pots I use organic mulch which breaks down to help refresh the soil.

Anybody else have experience with gravel as mulch? I've noticed a few self seeded plants growing very nicely between stones and pavers. One self sown columbine growing in those conditions must be four or five years old.

We have used pea gravel as mulch around a tree bed and in a lilly bed. This year we are pulling it all up. What we found is that weeds will set root in the pea gravel, so it didn't help much as a weed blocker. Of course, no weeds grew up through it. What happens is the weed seeds that are flying through the air will land in the gravel and take root. So they are usually easy to pull since they are only rooted in gravel. I had landscape fabric under the gravel. So I guess it depends on how many weed seeds you have flying around. If you are fully sodded, it will probably work fine for you.

We also tried the pea gravel as a walkway. The pea gravel does not float, but it does carry when walked on. So be sure it is in a bed that no one will walk in or it will be all over the yard. I never realized how many people drag their feet when they walk :).

In my yard, the parts that have a lot of sand added to the soil with a thick gravel stays moist a very long time. If its just dirt under, it doesn't seem to hold the water as long. I have three hills in back with good topsoil under the gravel and it gets pretty dry and hard. I think maybe its because the sand is easier to soak and you can soak it deeper? Not sure.

The gravel definitely pays off in winter. The drainage is good for the base of the plants and it keeps the soil warmer so I can stretch my zone and grow plants that otherwise would rot. Snow melts ten times quicker on the gravel than grass or organic mulch.

I think it probably depends on what you are growing. I gets pretty hot in summer on the surface so I imagine its hotter soil.

Gravel catches seeds too. Sometimes its a good thing, sometimes not. Personally, I love the gravel. I don't use any cloth or barrier under it. I keep it hand weeded.

The gravel in my yard doesn't seem to hold moisture any differently than the shredded mulch. The pea gravel does get more weeds than the larger stone. The gravel gets hot in the sun and so does the shredded mulch which is darker. The lighter color gravel reflects light while the mulch absorbs it.

The type of soil under the mulch seems to make more difference than the type of mulch.

After 3 1/2 years, I am still digging out "rock mulch" one of the previous owners put down. The hardest part was getting the weed block cloth out.

Years ago, someone put up a 10,000 sq ft metal building, one of those offered as "will finish to suit tenant" sort of projects. No one ever leased it. The savings and loan got. They failed, and someone else got it. Eventually, the city bought it cheap, and we finished it out as the new police station. During the original construction, the builder put in deeply gavelled beds all around, next to the building, and planted flotinia. I know for a fact that, for seven years, the water was cut off. After seven years, the flotinia was thriving and had grown tall. All it could have gotten was natural rain, including the very sparse rain of Texas summer.

That's interesting roselee. I have an area where we needed to put in French drains, and it was hard to grow anything except weeds.

So we made it a dry stream and covered it with gravel. Weeds sprouted up everywhere, so this spring I raked off as much gravel as I could, put down plastic and put down gravel again. I know the plastic probably holds in a lot of moisture too, and wondered if the woman in your article used any.

I cut around the two plants I wanted to keep, a yucca and a rue. There is an annual that pops up around the rue and I need to trim off those stalks, but the rue is lush and green. I know it likes dry conditions anyway, and the only water it gets is what is splashed across it when I water the two pots on the patio.

Everything on the west side of my house is dying except rosemary, and I am thinking of putting down gravel on that side as well, but without the plastic.

I have used pea gravel as mulch under my 6 citrus trees since about 1990. It does help keep the soil much cooler, and moist, as well as keeping the "weeds/grass" down considerably.
Jerry

Jerry, is it deep? I've noticed the weed solution depends on how deep the gravel is. I have good luck with keeping weeds down only in those spots where its like that. Where it is shallower, it doesn't help much. I am planning on another truck load this fall to fill some spots in thicker. The real deep gravel makes it hard to plant anything though because it runs down into any hole you dig like an hour glass.

I have a large sloped area where over the last few years, the gravel has gradually washed downhill and now mud covers the top layer close by after a heavy rain. I was thinking of using a thick layer of chat which keeps in place better and put the small river rock on as a top layer. I think thats what that crushed concrete stuff is called. Its very cheap too so I hope to save some money.

Can I use red lava rock around my newly planted lemon and kumquat trees