1. I would not bother with cutting the grass as close as possible. several planting beds I have created were better if the grass was simply covered over without mowing.

2. That is a good idea. The cardboard will block the grasses access to sunlight which will cause it to die and will allow the Soil Food Web to incorporate that organic material into the soil to feed whatever you plant there.

3. If you do not cut the grass short you will need some other source of organic material to cover the cardboard, although there are staples (for landscape fabric) available that could help some. Shredded leaves, when available, are also a very good idea.

4. Up here in Michigan (185 miles up from Indiana) the beds I created this way were ready for planting before winter set in so you should be well ready to plant next spring.

kimmq is kimmsr

concur, it will work fine but put more stuff on top of the cardboard. It should not be difficult to have some wood chips dumped on your driveway. Make sure you select the sunniest possible spot. Look at the tree shades now and imagine them longer.

Will it all decompose enough to be useful from an OM standpoint by spring, 2017?

the cardboard generally goes in one year (you will have to pick up the adhesive plastic strips from the pile). Wood chips, it depends: coarse, tree company chips will not go in one year, but fine, green ramial chips will go. at any rate it is not difficult to set the mulch aside, plant and cover again. grass clippings go in months but I doubt you will get enough to make a decent bed by next year. see if you can dump your kitchen scraps there (after they have rotted in a garbage can, ad mixed with browns to keep smells down).

I am a few miles south in DC. Normally, there would be a layer of finished compost on top of the cardboard. With that compost layer you could plant in the fall - maybe a cover crop like vetch and rye to add more organic material.

Without the compost you really are waiting for the leaves (shredded, I hope) and grass clippings to finish decomposing. I don't think you can get there by early spring, but probably in time to plant tomatoes in mid-May.

One suggestion - contact a nearby Starbucks for used coffee grounds to add in the fall with the shredded leaves. Your earthworms will thank you with lots of vermicompost.

As I wrote in my previous post here, "4. Up here in Michigan (185 miles up from Indiana) the beds I created this way were ready for planting before winter set in so you should be well ready to plant next spring."

kimmq is kimmsr

Just hold the cardboard down with rocks or bricks and as you mow the rest of the place, pile it on.

OR: in one area you could do trench composting. Lay out the veggie bed, mark off the rows and dig a narrow trench about a foot deep BETWEEN where you will be putting the plants next spring. Pile the dirt along the trench for refilling it.

As you accumulate kitchen waste (vegetable trimmings, coffee grounds, etc) fill a short section of the trench about half-full and rake the dirt back over the trench. It will be mounded up, and as the scraps decay, will settle. Next spring, there will be a layer of compost down there for the roots of your veggies to find. The year after that, shift the rows and plant over the old trench and start a new one between where the new rows are.

And there is always the "go a head and plant and see what happens". In late summer you can plant the cold-weather leafy greens: spinach, bok choy, chard ... with a bit of protection you'll have fresh veggies until Thanksgiving or longer.

Drmbear - I've done the same exact thing and the results speak for themselves. If you're not already, I suggest continuing to pile on the leaves! I like alternating leaves/hay (we have lots of hay), more leaves, more hay etc etc.

look up Ruth Stout, the Mulch Lady online. All I do these days is mulch and it's all I need.

No more tilling for this guy.

j

No matter where in the world you go you will find that soil is either sand, silt, or clay, or maybe a mixture of all three. Some of us have sand for soil while most have clay and few will have that most desirous soil, loam.

All soil types will be better with the addition of an adequate amount of organic matter, but keep in mind that there can be too much organic matter in soils and that can create problems as well.

Strive for balance.

kimmq is kimmsr

I've personally never run into a problem with too much organic matter providing it's well broken down.

j

I've never had it happen either Jerry, but it does happen from time to time.

Traditionally, it was most common in boggy areas, and sometimes in loam that already had decent amounts of OM. The move to walled raised bed gardens though, seems to have created more opportunity for problems resulting from excessively high organic matter content.

If the raised beds were created using mineral-based soils, it is less of an issue. However, we are seeing more and more cases of garden plantings suffering from too much moisture/not enough air.

Another contributing factor, it seems to me, is the bagged 'soil'/amendment industry. Many of the products are sold as 'soil', but a close inspection of the ingredient label reveals that most of these products are the waste streams of the wood/pulp industry, the meat processing industry, and even the municipal sewer treatment 'industry'. Now, each of these, when properly processed, can be perfectly fine amendments to a soil. However, when people are unaware of how to apply them properly, or are 'victims' (not really the best word) of misleading labeling practices, then these products can contribute to excessive organic matter content.

Basically... John and Jane Suburbanite, hoping to feed themselves and their children healthy food and create a little oasis all their own, engage in a little DIY and fall prey to an industry that is now largely in the hands of the big box stores. They want to keep things tidy in their little half acre, and build a few raised beds, as well as some nice perennial plantings.

They go out to Lowes, Home Depot, Walmart, or some of the other large stores staffed by sales people trained by the product vendors. They are steered towards the bagged 'soil' products which do not contain any actual soil at all.

Even the sq. ft. gardeners can fall into a similar situation with the over-use of compost.

Too much water-retaining capacity, not enough drainage nor porosity for air (CO2/O2, etc...) exchange.

Optimal levels of organic matter, not organic material, is in the 6 to 8 percent range, much more than that can create as many problems as people think it might cure. It takes about 10 tons of organic material per acre to raise the level of organic matter in soil 1 percent. I know from personal experience how hard it is to get the levels of organic matter in soil up to optimal levels, but have also seen gardens with too much organic matter in the soil that retain too much moisture and did not allow enough air into the soil. Plant roots need both air and water to uptake necessary soil nutrients.

Except for potting soil, soils are a mixture of the mineral component, sand silt, clay, and organic matter.

kimmq is kimmsr

I see this all the time online and question it - regarding "optimum levels of organic matter". PROVIDING THE OM IS WELL-DRAINING & SUFFICIENTLY AERATED (being key) a gardener can grow in 100% organic matter - there is zero doubt about this, and I'm referring to both gardening and potting soil.

My own compost is created from large amounts of leaf mold, horse manure, very large amounts of comfrey and household produce scraps. Since this compost is based on leaf mold it is light, fluffy, drains perfectly well and is well aerated.

Id like to know what issues can arise from growing plants in high levels or even pure OM. I've been doing just this for many years and my gardens couldn't be happier.

Most potting soils are also just that - 100% pure organic matter.

j

Well, I can't speak for kimmq, but as I hoped to discuss in my comment above, the problem isn't necessarily the organic matter itself, rather it is the conditions that can arise from too much organic matter. Too much lingering moisture, especially early in the season around the roots of seedlings and young plants, can lead to problems with the roots having adequate access to air. Roots 'breathe' - Well, they respire. If the water-retaining capacity of the medium exceeds the respiration rate (tied somewhat to growth rate) of plant roots, then the O2/CO2 exchange can become hindered. Soil is constantly allowing this gas exchange, but moisture can 'trap' expired gases, and water-saturated soil components can take up more room than is needed for air. If the medium reaches super-saturation, forget it, unless you're growing kelp, water reeds, willows, or plants that 'prefer' wet feet, they're done.

So, while mediums can contain lots of organic materials, if the materials don't allow for 'porosity' of air, as well as proper drainage/too much water retention, then excessively high organic matter can lead to problems.

Potting soils made from pure organic matter often have less problems, and while this isn't a comprehensive answer, simply put... in most cases they dry out very fast.

Well, heavy/clay soils ALREADY retain too much water, and OM can help those soils, too. It's complicated.

FWIW, I think in an in-ground, typical suburban, delapitated soil scenario, getting too much OM would be a difficult task even if you tried.

Yep, I agree with hairmetal. This is why I have never encountered the problem of too much OM. I live in E. Tn. and here, not only do we have clay, which is basically devoid of organic matter, but the hot, moist climate causes rapid decomposition. Organic materials quickly 'disappear' into their constituent forms. When I lived up North, a nice thick mulch would last all season. Here it's gone in 3/4 of a season or less.

Also, considering clay, not only can it cause poor drainage and 'soupy' water over-retention, but because it does lack organic matter, it will dry out very fast and become like concrete with no water retention capacity at all. It's a different situation, with different causes, but as with the organic matter, it's the conditions caused by these issues that are usually at the root of the problems.