Cement question

[Anthona]

A few years ago I had the front of my home cemented. I told the workers to leave a 3' x 3' opening for a possible shrub planting. Since then, every time I tried to plant something in that 'plot', the plant would die. i suspected a gas leak...but the gas company disproved that theory. Now, I want to patch up that opening. As of now, it has a low layer of red mulch on top of the soil that was originally there. I bought a bag of quickcement, Is there any thing I should know on how to go about this and trying to match the rest of the cement? Some neighbor suggested a crossironbar. I think its called. I've seen that being done whenever I pass a large mason job on some sidewalks...but others say its not necessary for the little spot that I have. Suggestions?

[hat]

---------------------------- New concrete will not "seal" with the old one, hence is the possibility of water seeping in between. If water freezes, it will expand and could cause damage to the new concrete (or the existing one)--uneven expansion will also occur in extreme high tempratures. Here is what I would do: (1) Dig the 3'x3' area until you reach stable soil--at least the 3-1/2 inch thicnkess of the slab. (2) Lay a grid wire in the bottom (or rebars--but this is an overkill). (3) Place (tar-based) exapansion joints on all four sides. (4) Pour concrete. On the other hand, if extreme tempratures are not an issue in you area, then you may use step 1 followed by step 4.

[Joseph Meehan]

Well a good soil test would tell you what the problem with the plants is. I suspect the soil is too alkali.

If you want to fill it in, the first question is will it be subject to vehicle traffic? Totally different needs for that.

One bag of concrete mix (not cement) is not going to cover 3x3 foot unless it is one mighty big bag. :-)

[spamTHISbrp]

The concrete will make the soil alkali, correct?

dave

[Eric in North TX]

Probably, the easy fix is vinegar, I pour some around my pine trees and they get so green it almost black. We are in an area with limestone as a base, alkalinity rules. I use a lot of acidy stuff to balance it out, but it wins in the end. The O.P. likely has a "caused" problem, much easier to fix.

[Goedjn]

If he dumps a bunch of vinigar in soil that's alkaline because of a cement pour, isn't he likely to wind up with a bunch of salt that will kill his plants anyway? Or are calcium salts not as lethal to plant life as clorine salt is?

[Eric in North TX]

Salt is salt, though if I had to choose, I'd take non-chlorine. I don't think he will get enough salt to kill a healthy plant. He could also op for an alkaline loving plant. I'm sure we are getting salt build-up, though it isn't a problem yet. Even watering leaves salt behind, fresh water has some. I mostly limit watering to drip irrigation, so that helps, but some full on sprinkler head watering is still required. I've tried just about everything else in the vegetable garden, with not good results, soakers, and drips never seem to let the plants get enough, so I combine purging my water filter with watering the garden for a win, win, lose.

[Phisherman]

Dig out 2 feet deep. Remove any rock/stone/clay and replace with compost/garden soil. You might have a large rock in there. Then match the conditions (sun/shade, moisture, pH) with a plant that matches these conditions and your climate. I'm sure there are numerous ground covers that will work well, although there's more choices with a sunny location. Or, you can set a potted plant on top of the mulch.

[Anthona]

I appreciate the info on how to replant...but that was not the intention of my post. I want to cover it up permanently.

[Goedjn]

Metal deckplating, then.

[Anthona]

Thanks again, but it would be helpful to some of us who are ignorant in terms of cemment among other tasks, to know what is "Metal deckplating"? I did a search and all I got was something referred to those large semi's trucks. What is it, and where can I get it if I go that route?

[Joseph Meehan]

Well you can still use the first part of the advice. Digging it out at least two feet, is the first step of putting down concrete that will not sink move or breakup in a short time. However stop there and used crushed stone compacted well in a few layers to make a good foundation for the concrete.