Isn't peat moss supposed to help the material hold water? Clay already holds water, sometimes too well, so I question the adding of peat moss. Is that just to make the soil fluffier? I would say add more compost and aged manure and things like that if you want to till it into the soil. What many of us find very effective is to make lasagna gardens (See the soil forum, or there is a post in this group about it, too.) That concentrates the good stuff in the area where most of the roots are, and then you don't need to worry about your clay soil. It will be drastically improved over time by using lasagna beds on top of it.

Or if you want to stick with the tilling method, add a mulch of leaves in the fall with manure on top. Both of those are easy to find free. Till that in each spring, and in a few years your soil will be SO much nicer. You can certainly topdress with aged manure or compost during the growing season as well. DO NOT put peat moss on top of the soil, that doesn't work out, it forms a layer almost impermeable to water when it dries out.

Marcia, who also has a heavy clay soil

How much work do you want to do each year? For years I labored with my heavy clay soil. Tilled it up, hauled in truck loads of compost and worked that in, then hauled in more truck loads of compost and left that sit on top. Within months of planting the garden the soil was rock hard and the compost nowhere to be seen.

Following year I did the same thing, and the next.

Then I started mulching in addition to the compost and this was better as the soil no longer got hard as a rock and retained water better (as you know, clay holds water well, but still dries out in summer).

After awhile I figured there had to be a less labor intensive way. I was heavily influenced by Square Foot Gardening and started incorporating the ideas, but eventually just stopped growing in the ground and made raised beds and filled them with no soil. Just compost, peat and vermiculite. It wasn't cheap, but I haven't looked back.

No more laboring to make crappy soil great soil. I just built raised beds with nearly perfect soil to start out with and now I am done aside from a little compost each year.

So, if you wish to continue laboring with the soil, consider mulching as it does wonders to keep the soil in shape between compost applications otherwise go to raised beds and fill those beds with the highest quality ingredients you can.

All clay soils need to be better soils is the addition of organic matter, compost and any other organic matter you can get except peat moss which is a non renewable resource. In Wisconsin, like in Michigan, you have fairly readily available large quantities of tree leaves every year, a rewnewable resource, that can be used to make compost, make mulch, improve soil, but you need to get enough. Most people simply do not add enough organic matter, especially at first.

All clay soils need to be better soils is the addition of organic matter, compost and any other organic matter you can get except peat moss which is a non renewable resource.

It just floors me that you keep making this ridiculous and false claim about peat moss despite the number of times you have been educated on the topic.

I second Justaguy's recommendations of raised beds and mulching. Shredded leaves are your best friend. Add them all season as they break down and they'll help soil.

This fall- if you have the time etc- try a raised bed. You can mix in existing soil, compost, 1/2 finished compost- whatever you have laying around. Top it off with shredded leaves and it will be perfect in the spring.

I also agree on mulching the planting beds during the growing season with whatever organic material you can lay your hands on. Repeated applications of OM - be it compost, leaves, grass clippings, whatever - will all add to soil tilth and can offer benefits like weed supression and conserving soil moisture during the growing season. If raised beds are not your cup of tea (and they are not uniform in their appeal or their suitability), then plant a green manure cover crop after harvest. Any organic matter worked into the soil will help to condition it and loosen the clay.

Achieving great soil tilth is not a one time shot but an ongoing process - each season will get better and better.

Peat moss is a non renewable resource and now the Royal Horticultural Society is recommending to its members that they stop using it because it is a non renewable resource. It takes somewhere around 200 years to make a few centimeters of peat moss and no matter what the industry tells you about harvesting peat moss not destroying habitat, it does. Justaguy2 I am sorry that you are unable to accept this simple concept.

Peat moss is a non renewable resource and now the Royal Horticultural Society is recommending to its members that they stop using it because it is a non renewable resource.

As has been pointed out to you numerous times, the peat harvested from US and Canadian bogs is harvested in a sustainable manner, is regulated by the government as such and it doesn't take hundreds of years to recreate using modern management techniques. Current harvest rates are exponentially less than the growth rate which means the amount of peat is increasing, not decreasing.

But, you have had this explained to you by multiple people in this very forum numerous times already.

The Royal Horticultural Society is dealing with issues on the other side of the pond where it is my understanding there are environmental concerns.

The OP in this thread is from Wisconsin so I really doubt s/he is getting peat from Britain.

Only about 5% of the mapped Canadian peat reserves are harvested, allowing total peat reserves to grow at a rate 60 times faster than that which is harvested. And even harvested commercial bogs are now currently being seeded and farmed, so that this most definitely is a very sustainable and renewable resource.

Peat bogs and fens in the UK and Europe have been harvested for many centuries - and not just for agricultural purposes; peat is/was a prime source of fuel - compared to the less than 100 years of the Canadian peat industry. And these bogs/fens constitute only a tiny percentage of square footage compared Canadian peat real estate. Yes, it is not sustainable or renewable from these sources, but as justaguy notes, not too many of us go to the expense and bother of importing peat when it is so plentiful here.

While it doesn't tend to be at the top of my soil amending choices for other reasons, no one should feel guilty about purchasing and using this product, thinking they are contributing to the demise of ecosystems and the downfall of the environment. I'd rather a little peat used than another flippin' housing development ravaging the countryside!

Watching Kimmsr claim over and over again that peat moss is non-renewable reminds me of the conspiracy theorists claim that the US government flew planes packed with explosives into the WTC.

No matter how much you debunk their theories, they'll still pop into every thread to claim it anew like it is gospel truth.

Alfalfa is an excellent soil conditioner. It adds organics to a sandy soil and is an anti-compaction agent for clay soils. It holds up to 4 times its weight in water and is high fibre, so an excellent alternative to peat moss. Plus peat moss does not rewet well, and alfalfa does. Also, peat moss is acidic at 5.0 pH and alfalfa balances alkalinity and acidity bringing soil back to 6.0-6.2.

jlaak: count yourself lucky to have clay soil rather than sandy soil -- its nutrient-holding capacity is many times greater. I would simply maintain a mulch of shredded leaves and let the worms do the work of incorporation. By the way, my view of peat moss is that it has little nutrient value, unlike leaves, and costs money, unlike leaves. I'm not one of those who believe that only something that takes lots of labour and money has value! Regards, Peter.

I am not the only voice in the wilderness and I have not said anything about any conspiracy, although the advocates of using peat moss seem to get quite violent in their attempts to refute the simple fact that peat moss is a non renewable resource, that harvesting peat moss is non sustainable. As I recall there was a world wide conference held in Iran in 1971 that stated then that peat moss was a non renewable resource and that harvesting of peat moss was not sustainable and habitat destructive.

Here is a link that might be useful: Linda Chalker-Scott on peat moss

I work with clay soil in my area and have had great sucess with adding lots of leaves. I try to build up a good 6 foot layer or more of dry fluffy leaves in the fall. By spring this has compacted down to less than a foot. Some people layer that with newspaper and or cardboard in an attempt to keep weeds from sprouting but I find that the roots of the weeds that make it are so loose in my leaf beds that pulling them is almost a pleasure. Keep in mind that leaves break down slowly and will suck up lots of nitrogen from the soil. If your going to use lots of non composted organic material you will need to be looking for a nitrogen source. All my cold coffee and coffee grounds go right onto my plants. Coffee can burn your plants but I don't have any issues with that due to the amount of leaves and how quickly they lock up the nitrogen then slowfeed it to my veggies. On another note a friend of mine has been layering newpapers, cardboard, and about 6 feet or more of leaves every year for the last 3 years. As a favor I double dug his garden this year to a depth of about 18 inches or so. The soil is beautifull this year and the clay has been incorporated into a nice balance. I noticed while digging that all the worms were in a zone of about 6 inches where the clay and old rotted leaves met. To my understanding the worms break down the leaves and give the soil a healthier structure so I think this method of building a dense organic layer then mixing in the clay really worked out. His bed now has 18 inches of roughly 80% orgnaic material and 20% clay soil and now that will be build upon with more leaves this fall. I think its important to maintain the mineral content of the soil and not go 100% organics but thats a personal take on the situation. BEST OF LUCK TO YOU

Wood chips have worked best for me. It breaks up the soil very well keeping it loose and fluffy. It put them it the path between the raised beds during the summer then till the garden level in the fall. By next spring I can raise another bed with a rake or mantis if I need to go deeper and add more chips at a deeper level.
Keep the actual spot for the seeds and young plants free of wood chips for a number of reasons. Yes you will need more nitrogen at first until the worms start to turn the tables on using more nitrogen than is being produced.
Lots of water will keep that process moving quickly and mulch over the top around plants with whatever else is handy.

I agree, with smallaxe, Kimm and kralen FWIW. Wood chips and leaves are absolutely gardener's gold for my Michigan clay soil.

Justaguy, I'm sympathetic to your clay soil situation. It does take a LONG time, with alot of amendments over the years, to get that clay soil friable doesn't it?!

I hate to disagree with Kimm but his take on peat in North America is wrong. Peat is sustainable in North America and this is basically an irrefutable fact nowadays.

As to Chaulker/Scott - she makes many overblown statements in her myth papers IMHO.

One example deals with her conclusion that bone meal is detrimental to plant growth due to its inhibition on beneficial fungi growth.

The detailed study below shows some basis for her conclusions but the bonemeal was not nearly as detrimental on beneficial fungi as she opines IMHO. In fact, in one test bone meal was beneficial for fungi innoculation!

Plus the fact that bone meal can help grow plants in and of itself. Well at least it has always helped me in my gardening as well as millions of other gardeners.

Look at the last paragraph and see where bone meal, peat, mineral soil and innoculated fungi WAS NOT detrimental to fungi innoculation. So sometimes bone meal might reduce fungi development, sometimes increase it, sometimes nothing - but to say that it prevents fungi innoculation is way overblown IMHO. This is typical of Chaulker/Scott IMHO.

Not that bone meal is required, this is just an example of Chaulker/Scott's exaggerations. Do not believe, at 100 percent, everything you read from her myth papers IMHO.

Quote:
Mycorrhizal inoculation of organically grown tomato plants

Siri Caspersen
Department of Horticulture, Swedish University of Agricultural Sciences, Box 55, SE- 230 53 Alnarp, Sweden

Improvement of plant nutrient uptake and protection against root pathogens by arbuscular mycorrhizal fungi (AMF) might contribute to a reduced utilization of soluble fertilizers and pesticides in agriculture and horticulture. For organic cultivation of glasshouse crops, regulation of nutrient supply and of the balance between nutrients is a major challenge. Common nutrient sources are green and animal manures together with plant and animal residues from the food industry. The recommended soil nutrient levels for glasshouse cultures are gerally high and based on easily available nutrients extracted by water or weak acids. Thus, for P in particular, luxury levels are common in the soil and the risk of P leakage is evident.

When tomatoes are cultivated organically in the same soil for consecutive years, root pathogens may also become a problem. Root colonisation by mycorrhizal fungi in combination with the use of slowly soluble P- sources might be desirable both for bioprotection against root diseases and for a reduced risk of P leakage. However, establishment of mycorrhizal root colonisation is difficult due to the normally high soil P concentrations in combination with a widespread use of peats, which have a low P- fixing capacity, for pH regulation and for soil structure improvement. The aim of the presented work was to investigate the influence of organic and slowly soluble fertilizers and of inoculation with AMF on mycorrhizal root colonisation and on plant growth and nutrient uptake of tomato (Lycopersicon esculentum cv. Delito) plants grown until planting stage (six weeks after sowing) in soil- or peat- based substrates.

In sterilized soil: sand (1: 1, v: v) amended with apatite and bonemeal, we observed a strong plant growth response to inoculation with an isolate of Glomus intraradices. Plant growth was lower and the mycorrhizal response stronger in pots where the slowly soluble Psource apatite was added alone in comparison with pots where apatite and bone meal were added together. Mycorrhizal root colonisation and sporulation were reduced by the addition of bone meal. The positive response of plant growth and nutrient uptake to mycorrhizal inoculation in the soil: sand was probably related to an increased P uptake of the mycorrhizal plants.

The effects of inoculation with Glomus intraradices (BEG87) and addition of bone meal and/ or blood meal were investigated for tomato plants grown in a substrate containing mineral soil and peat (4: 1, v: v). Root mycorrhizal colonisation was high (60- 80%) in pots containing either bone meal or blood meal or none of them. When both fertilizers were present, however, AM fungal colonisation was reduced. Inoculation with G. intraradices increased shoot dry weight in comparison with the uninoculated plants for all fertilizer combinations, and in particular for blood meal alone where no growth response was observed for nonmycorrhizal plants. It is possible that an AMF- mediated increase in plant the uptake of P was necessary for a positive effect of blood meal on plant growth. As the mineral soils in the substrate had been partly sterilized, however, introduced microorganisms were probably quite important for the mineralisation of bone and blood meal, and effects of other microorganisms associated with the AM fungus on plant utilization of the organic fertilizers can not be excluded.

End quote.