Go with the manure versus mushroom. Does the same job at half the price plus mushroom bagged stinks.

Here is a link that might be useful: Propagating Perennials

linnea, mushroom compost is higher ph, and higher in salts that may be harmful to tender young seedlings (and may inhibit germination of seeds)...it's best dug into beds, and at no more than 1/3 the volume. On the other hand, composted steer manure blend (steer manure + decomposed wood chips) at Home Depot for $1 bag has been so well composted and aged, the last few years I've bought it it's been odor free...so you know old. The mushroom compost can be a good additive, but not for salt sensitive or acid loving plants - contains lime.

Here is a link that might be useful: Cautions mushroom compost

Interesting. I never knew the mixes were so complex! I thought it was just newer manure vs. "used" manure in the case of mushroom compost. Why do so many people seem to want the mushroom version, then?

I donÂt know what pH my soil is: itÂs former Midwestern farm land, black dirt on top, yellow clay a foot down. I donÂt grow any acid loving plants like anything in the rhododendron family (or blueberries). Since I have used this mushroom compost for a couple of years, has it made my soil more basic, then? The topsoil was amended with peat and much compost when the bed was made 4 years ago, and a new layer of manure and bark chips every spring.

Just a slightly different take on this. Bagged manure available around here from the box stores has a VERY low content of actual manure -- in most cases only about 10%. Yes it can provide some tilth to the soil but very little in terms of fertility, and in my experience does not really add much to the soil. Mushroom compost, on the other hand, is made up virtually completely of composted manures and has a much higher organic/manure content than the bagged manures available here. Unfortunately, where I live mushroom compost is virtually impossible to find, none of the stores sell it and it is no longer available in bulk any where in SE Michigan that I know of.

I did manage to get one load of mushroom compost about 5 years ago and used it as a soil amendment in areas where lime loving plants grow, like hellebores and clematis. Those plants grew like crazy! I know it is somewhat basic but that can be corrected depending on what you are growing and your natural soil pH. I know at Ashwood nursery in England, probably the premier hellebore nursery in the world, they made beds largely of mushroom compost, and their hellebores in the garden were to die for. So....take from that what you want, but wish I could get some more mushroom compost.

Having said all that, if you have made beds the way you describe and are adding that much organic matter every year, your soil is probably in great condition and you probably only need to amend or fertilize around hungry plants (clematis, roses, hellebores....)

BTW, dehydrated manures are sometimes available bagged, and while much more expensive than the box-store bagged "manures", add much more fertility and tilth to the soil IMO.

I bought mushroom soil years ago from stone and soil yard. I had a choice to buy the compost straight or have them mix it with their soil. Since I needed all new stuff to fill a raised garden I opted to have them mix it. A year later I took a sample to our local extension and all the numbers were extremely above normal, like 4 to five times the upper limit for normal. I was not too happy about that, but the plants do seem to be doing fine. :c) And yes... it was slightly alkaline and soil is usually acidic here.

I suppose I should test the pH of my beds but since itÂs all former farm land I figured it would be ok. Though the main one is a 2 level raised bed which had to be filled with a load of topsoil when it was built. I didnÂt ask too many questions about where the new topsoil to fill it came from, but around here itÂs usually from the many new housing developments that are/were being built: all on the same farm land. We amended the soil, replanted our perennials but have added compost every year since. It has been 4 years but itÂs still sinking. The lowest tier (1 foot of the ground) stopped sinking last year, but the highest level (2 ½ feet above the ground) is still sinking.

I donÂt want to replant all those perennials so have added compost gradually so (hopefully) they will adapt to the gradually rising level. It seems to be working fine.