The microherd is what breaks down organic materials. So, by the process of improving the organic component of your soil you increase the number of microorganisms. In addition to your manure, you may want to use more organic fertilizers. Compost. Adding those materials to the soil will attract the microorganisms. There is a very nice primer on the soil biology (including the soil food web) at the NRCS Soils Website (see link below).

But, without a good soil test, none of it matters. I think you had one last year, maybe the year before?

Here is a link that might be useful: The Soil Biology Primer

Jim, just some random thoughts:

Organic gardeners use the slogan, "Feed the soil, not the rose". If you like slogans, maybe you could amend that to "Feed the soil, not the microorganisms".

If you really want to buy microorganisms, the new Scott Miracle-Gro and the new Espoma "Tone" products have them. I'll bet the new versions will be hard to find in local stores, at least for a while.

I agree with Diane nj about the soil test, but you should have definite goals in mind. The usual soil test is designed to tell a farmer how much of each nutrient he needs to purchase in order to make a profit on his crop. This isn't exactly what you, or most rose growers, really want to know. You want to know how to improve your soil so that you can grow the best possible roses. Why not bring a soil sample directly to a state extension service and describe your goals?

Perhaps your soil is not coarse enough, see:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TC3-4TCXGHX-2&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0amp;_userid=10&md5=94755eca145480902bd3a3222524c21d

Here is a link that might be useful: link to research paper

You need to add organic matter. Aged manure is terrific, but by no means your only choice. You also don't really need to add microorganisms since their spores are in the air all around us, and also in the air in the soil. Once you add food (the organic matter) and a little moisture the spores will germinate and the microcritters will eat your added organic matter. All the Espoma "tone" fertilizers work on those principles, and they're what I use in my gardening.

The more organic material you add, the better. It's going to be almost impossible for you to add "too much" - ever.

It's the ideal soil amendment. In a soil with a lot of clay its clumps end up aerating the soil, making it easier to work and easier for roots to grow in it. In a soil with a lot of sand it increases the soil's ability to hold water, likewise making the soil a better soil for most plants. In both cases the added organic matter makes the soil more of a loam soil, the one in which most plants grow most easily.

Oh, one of the big benefits of using a mulch of organic materials is that the mulch decomposes, adding its organic material to the soil as it does.

Compost.

My Dad used to say my Grandma would always have him bury the fish heads around her roses.

Today I make 'tea' out of the remains after the fish are cleaned. Just like manure tea it helps if you aerate, so I just keep them in a WELL covered barrel and spray with the hose, mixing vigorously as often as I remember. I use it diluted, then add more water to the barrel. Nothing left but a few bones after a while.

Lots of people use seaweed even as a mulch.

Bird droppings.

Do you recycle kitchen scraps, yard and garden stuff into compost, to give back to your soil?. It doesn't have to be complicated. :)
Donna

Compost, coffee grounds, eggshells, orange rinds, clippings from non-chem lawns, fish emulsion (or whole fish), alfalfa pellets (make sure not salted). These will encourage your native microorganisms to thrive. Repeated applications of fungicides & pesticide spray, 3-iin-1 products and the like are the enemy and can destroy biodiversity in your soil Promoting soil health is one reason some rose gardeners don't spray, and therefore have to choose varieties very carefully.

I've been composting heavily for quite awhile amd I turn up worms with every shovelful. I also know of some who garden using fertilizers (swearing by 10-10-10) who don't have a worm around.

I for some reason put more emphasis on texture or in many spots in my garden with shallow soil raising the level. I have also used grass clippings on top of newspaper. And Rose Tone. Occasionally Composted Cow Manure and some Milorganite.

Then I have several old coompost piles that have been lying there overgrown with vines, covered with fallen tree branches and otherwise somewhat inaccessible. In short I have been too lazy to get at them. I promise to do that whenever the soil thaws.

I've had at least a couple of soil samples done by Cornell that I find not very useful. Both have come back with the conclusion that NPK is high. Organic level 4.6%, no comment as to whether this is high, low or adequate. The analysis posted on GW brought a response that the iron level, 7#/ acre, was low. Have been adding iron lately that seems to help. I notice in checking the last one that the pH is on the low side, 6.2. Might be a problem so will add lime again.

Anyway I'll give a lot more attention to adding organic matter!

Organic matter. Compost. More organic matter. More compost. OM and compost fix pretty much whatever ails your soil.

Good sources: horse manure is ok. Composted chicken manure is better. Also rabbit, llama/alpaca, sheep, goat, cow. In roughly that order of preference.

Worm castings are excellent. Don't need to add much. Alfalfa meal, fish products, kelp/seaweed. Marine stuff tends to add more micronutrients than terrestrial stuff. Grass clippings, shredded leaves, coffee grounds. Homemade compost or alfalfa tea are excellent sources of both OM and the microorganisms themselves.

As mentioned above, the microorganisms are already there. They just need to be given a reason to live - food, moisture, decent pH, decent drainage. 6.2 is on the low side, but not horrendous. 4.6% OM is decent, but more is better. Avoiding insecticides, fungicides, herbicides, and synthetic fertilizers will help build up soil microorganism populations too.

Well, I hope I haven't been dumb.......but maybe someone can tell me if I have been.

I put Roundup on a grassy area and let the grass die. Then I dug it out and put some of it in my compost pile. I kept wavering back and forth about putting it in there but it was all dead so I thought it would be ok. I was under the impression that Roundup didn't "stay in the plant's system" or something like that? Did I doom that pile of compost?

Texaslynn, there is surely some amount of Roundup in your compost pile, either in the soil or in the plant tissue you moved from the grassy area. The bad news is that Roundup has an average half-life of a month in soil and this can vary up to 5 months or more. The better news is that Roundup appears to bind so tightly to soil that it is not taken up by plant roots. That's the reason why many crops can be planted either just before or just after a field is treated with Roundup. How reliable is all this? Well, if I had to bet money on the safety of your compost, I would bet that it's safe, but If I had to bet my roses on the safety of your compost, I would refuse the test.

Yikes!

Thanks, Mike. Well, the pile is a new pile, just started and fortunately I put all the grass on the very bottom. I have about two layers of manure and leaves on top of that (so far). This compost won't be used for another 8 months or so and maybe I'll just avoid that bottom layer - if I can remember by then what's down there (of course the bottom layer is always the "best", too - dad nab it!)

The last ARS Rose Annual has a great article by John Mattia about making tons of compost out of tree leaves and grass clippings. He deals with the Roundup problem by letting the process take several years--he is more interested in quantity than speed, as he grows well over 100 exhibiton HTs.