I lost 3 Azelas plants due to the clay soil never drained When we dug up the dead plants the hole were filled with water and now we dug up the entire bed about 3 feet long by 3 feet deep we are going to pu rocks in the bottom and sand and soil anything else we can put in to grow some plants live in South Carolina

Hi John, and welcome. For advice on amending clay soil I'll call on our expert @RickCorey who has vast experience with this.

Good luck, and if you can post some pictures of the area you're working on, that will be very helpful, too.

@johndriesse



Please don't put the rocks in the bottom of your bed. You will be creating a perched water table. I learned about that from @sooby.

I've just put a call out to her in this response and she can explain it to you much better than I can.

Is it natural clay or added clay as often found where new houses are built?

Either way one thing you can try, no guarantee, is get a large post hole digger and after you have dug out the bed drill holes for each plant as deep as you can.
I put in a decorative garden in an office area and we used a post hole digger for each plant putting planting soil in each hole.

If you have the money and want deep holes hire a company with one mounted on a skid-steer; they will give you deep holes.

RoseBlush1 said:

Please don't put the rocks in the bottom of your bed. You will be creating a perched water table. I learned about that from sooby.

I've just put a call out to her in this response and she can explain it to you much better than I can.

What happens is that water doesn't cross the interface between fine material above and coarser material below until the upper layer becomes saturated. So rocks and gravel at the bottom of a container or similar situation actually impede drainage rather than enhancing it. The fill needs to have the same texture throughout.

Having said that, digging out the clay can create a "bathtub" that still won't drain unless maybe going three feet down got through the clay layer. It's often better to make raised beds. If you pour water into the hole now, does it drain away well? If not, you may need to figure out a way to make it do so, I'll leave that for Rick.

Another thing to consider if you want to plant more azaleas is that you need to make sure the pH of the planting material is sufficiently acidic.

Hi & welcome!

Adding organic matter (to the surface, the way mother nature does,) & the passage of time will improve your soil, by texture, fertility, and drainage.

Dr. Ingham can explain much more precisely than I can:
http://permaculturenews.org/20...

We had the worst red clay you could ever imagine when we moved here. There was not one tiny bit of good soil at all. My husband found out very quickly when he tried to plant stuff for me that if you add good stuff to the hole, the plant roots don't want to leave that good stuff and you create a bowl of water that won't drain underneath it. We had many, many plants (including expensive trees) that died due to that. I know how hard it is to wait, but we have found that adding the organic (good) stuff on the top is the best. Yes, it has taken a long time and no our soil is not gold yet, but it has improved a whole lot. We also do trench composting and have found that for us, it is working really well.

When faced with the same dilemma I approached it in two ways. I put in a raised garden after finding out (the hard way) that it was virtually impossible for me to dig enough clay out to be meaningful. The raised garden began as a 1.5' deep x 8' x 12' garden, and then two years later it was expanded to 2.5' deep x 12' x 20'. I did all the work myself. When I decided to put in an extensive landscape three years ago, on the back property line, I hired it down. There were scrub trees to take out and their roots to be removed..........heavy equipment. There was clay to dig out, some 40-50 tons of it..........heavier equipment. The clay we have is incredibly dense and heavy. Then there was all the yards and yards of garden soil/topsoil/mulch to be brought in. Then plantings had to be done in that 150' x 8' area.

This is what all that looked like as time went on:

03/2014


07/2015


03/2016

johndriesse said:I lost 3 Azelas plants due to the clay soil never drained When we dug up the dead plants the hole were filled with water and now we dug up the entire bed about 3 feet long by 3 feet deep we are going to pu rocks in the bottom and sand and soil anything else we can put in to grow some plants live in South Carolina

Hi John! Welcome to NGA.

First, it's true that raised beds solve the heavy-clay-doesn't-drain problem. You could have standing water an inch deep over your whole yard, but if that raised bed stands 12-18 inches above grade, you could WADE out to that raised bed and still grow fine crops!

But suppose you want to rescue some deeply amended beds that you just dug recently.
There are drainage solutions that go DOWN instead of UP, if you like digging trenches.

The problem is that water just doesn't perk fast enough through clay like ours to rely on drainage THROUGH the clay.
Once the hole fills with water, roots drown, just as you would if you buried your head under water or under mud, or even under water-saturated soil or clay.

When you dig a hole in heavy clay, it doesn't matter what soil amendments you put IN the hole, because that hole is going to fill with water. You could entirely replace the soil with anything you like: after the first rian, it will be waterlogged and stay that way for days or weeks.

The hole in the ground (anything BELOW GRADE) works like a bathtub: any water that enters, stays right there until it evaporates. You could fill your bathtub with pure Perlite and gravel, but it would still be waterlogged and no air could get down to the roots.

Water excludes air, so the oxygen that the roots need to live has to TRY TO diffuse through waterlogged soil.

Well, oxygen CAN'T diffuse fast enough through water or water-logged soil to keep roots alive. Gasses diffuse literally 10,000 times faster through air than through water! For a root zone to NOT kill roots, air has to enter the soil. Then more air can diffuse 10,000 times faster, and keep roots alive.

For air to enter the soil, water has to leave it. Good aeration is almost the same thing as good drainage.

Since water can't perk through heavy clay fast enough to keep up with even a light rain, water needs some other way out of that hole you dug.

Unfortunately, what with gravity, water only flows down. That's fine for draining the soil ABOVE, but when a hole is below grade, it would have to flow up to get out.

Instead, you have to give it an exit path that is entirely DOWN.

Whatever the low point in your planting hole or bed is, call that the "floor".
To drain the hole or bed, there has to be a trench (or pipe) that starts slightly BELOW the low point of your floor.
And that trench needs to slope uniformly DOWNWARDS if you want water to leave the bed and go somewhere else.

I just cut thin, shallow slit trenches as wide as the blade of my mattock (2-3 inches). I don't even backfill my slit trenches with gravel. The clay is so hard that they hold their shape like tiny concrete trenches.

Or you can dig a wider, deeper trench and bury perforated, corrugated plastic drainage pipe and backfill the rest with (heavy, expensive) gravel.

But you need a point that is lower than the floor of your planting hole, to encourage the water to flow down TO.
If you don't have a slope or grade or low point to guide water towards, raised beds are the only drainage answer I know.

If you are lucky and the clay is only a thin layer that you can dig or drill THROUGH, you might drain a hole by digging down into a better-draining layer. But often clay layers can be hundreds of feet deep!

@drdawg / Ken that is beautiful. Could not ever tell now that was just hard clay before. Good job

I also have bad clay soil, so you've inspired me to do a raised bed similar to yours, Ken. It's beautiful and secure so the critters won't get your goodies. That's exactly what I need.