Yesterday I got my delivery of 1m³ of compost (I was excited like a child with a lollipop lol ) to improve my heavy clay soil.






As you can see I topdressed the 4 raised beds because I already had plants in it and didn't want to disturb their roots now that they've begun growing (I'm surprised my lavender survived the wet winter in that). However, since it's still clay soil, I'm not sure if I was better off working it in with a fork...I would do it like that in the non-planted ones.

Before I mulched with compost I used my grass mowings, but that was hardly enough to get the weeds at bay...

Opinions?

That is a tough question since compost is so valuable - soil structure or nutrients? Can you loosen up the top 6" to 8" of your clay with a pitchfork or shovel? Not necessarily digging and turning over but loosening (less work). Then I would put the compost on top like your other beds. Clay is really tough to loosen up with compost because compost would continue to break down. There are probably lots of nutrients in your clay but hard for plants to access.

my goodness, you're in Bilzen? I would LOVE to be in your part of the world right now! I'm a cycling fan and will be awake watching Amstel Gold at like 5:30 my time tomorrow morning.

I really like your beds and honestly the exposed clay I see in your picture reminds me a lot of what I have in my yard here in Tennessee. I think you should focus on top-dressing the bed with compost over time...because feeding the plants will give them the vigor necessary to spread roots and succeed in that environment. If at all possible try to encourage earthworms to come in and break up that soil as well. I would be concerned about harming the integrity of your beds if you started digging around inside.

Is Bilzen that famous? :p Well I'm not a fan haha; I actually hate it. Those guys have no respect for the rules of the road around here!

Well I already worked in some potting soil and sharp sand through it last summer before planting, but drainage hasn't really improved because of that. Anyway, I'm trying to get my own composting factory up and running to supply myself each year for topdressing.
And yea as you said, mulching is perhaps better in already 'established/planted' beds. I also dig up some worms from the back of the shed and move them to the raised beds to lend a helping hand :p I'd be surprised if they moved from my lawn to the beds themselves as they need to dig underneath the wall.

Your relocated worms would love the compost top-dressing - it's supposed to encourage more worm activity.

Used coffee grounds also attract worms. They also add nitrogen and organic matter and (until they break down) open up the clay a little tiny bit.

I would agree with Cindy: if the clay is soft enough that you can scratch some compost into the top 6-8 inches, do that. It will make those 6-8 inches a l8ittle more open to letting oxygen diffuse down, and will retain more water.

It will also decompose faster than top-dressed mulch would.

Even the beds with plants already established could let you scratch the compost in a little between the plants. But it sure looks nice as it is, and it WILL decompose over time and the mineral nutrients will eventually reach the roots.

>> I'm not sure if I was better off working it in with a fork

When you have your own compost pile going, you can have the best of both approaches: do both. Turn in as much finished or near-finished compost as possible every spring and fall.

AND top-dress with 1-2 inches of compost (finished or near-finished or just started) and/or mulch (coarse) a few times per year after the plants are in.

After you've added enough compost for enough years, top-dressing with compost or mulch will be enough to MAINTAIN soil structure. It helps drainage and aeration that you added sand right at the beginning and mixed it well. Mixing in crushed stone, grit or screened bark 2-4 mm in size will also help create drainage.

But, if you don;t provide and maintain enough compost, the clay will revert to clay or concrete.

That all sounds great, I think you are on the right track! Don't underestimate your worms, you never know where you will find them after a hard rain

As far as cycling goes, I don't blame you. I don't ride much anymore because most of the folks I encounter on the bike drive me nuts. I can only imagine living in the middle of it all, so to speak.

Hi Lee-Roy, have you enlisted any gypsum to help break down the clay? If not, you can use 1 kilo per square metre and of course it doesn't alter your PH.If there are any horse stables in your area, or across the border, do a Sunday drive.Horse manure contains so much partially/decomposed hay (but also weed seed) and the worms love it, so will your dogs! Build up your worm population and let them do the work.

Whenever the dirt is disturbed, it negatively affects the drainage and microbes, temporarily. Unless installing plants or removing unwanted ones, I try to not disturb the soil, even in dead spots where I've just pulled up grass. Without human intervention, organic matter (besides dead roots) would never be under the surface. The worms & microbes are best able to do their job when things are "normal" and undisturbed.

A 15 min vid that explains these things much better than I can.
http://permaculturenews.org/20...

Would surface mulch/compost application entice worms to come up closer to the surface of the soil where a lot of plant roots are located?

Most definitely, the only problem I have with that is that it gets the worms near the surface (they congregate in the roots of my daylilies) then all the critters in the neighborhood come to feast on them, and they dig up my plants toss them to the side and I end up replanting things almost every morning. Still, I love having all the worms working my soil.

Absolutely! That's the natural way for worms to access OM. Their digging/tunneling is part of what helps improve drainage, and they drag some materials under the surface. They know what to do.

Larry - I never thought of the downside of surface amending.
I so prefer the worms working my soil than hard labor on my part.