Re: CULT: Raised Bed Soil Too Light

Anner -- Both Clarence Mahan and I have used a couple of inches of mushroom soil tilled in as an additive to garden soil with good results. Too much of it, I suppose, could produce a bed that stays damp too long. But we only used it as an additive. It is very, very light stuff. The difficulty for me, however, is that the nearest source of the stuff is about 2 hours away. The cost of truck rental really outweighed the cheapness of the soil. For the last 3 years, for raised beds, I have used both of the following:

1. Garden soil turned, then 6-8 inches overlay of commercial topsoil added, then 2 inches of concrete sand on top of that, then all tilled in. Of course, you can mix it first, if you prefer and have the facilities. The topsoil is commercially produced and is composed of equal parts dirt, sand and composted leaves (sometimes called leaf mold). The fellow I hire to deliver and spread the mix used to shake his head and ask why I was adding sand to a mix already containing sand. The answer is that, over the years, I have seen the commercial-mix-plus-garden-soil-only turn hard as a rock (well, almost) in just a season. The additional sand has made my beds very friable, has improved drainage, and the iris love it.

2. Garden soil excavated to a depth of 8 inches, discarded or used elswhere, and replaced with a raised mound of commercial topsoil plus 2 inches of concrete sand. Same results: happy irises.

My test for density of soil is this: If, when the ground is dry, I can't poke a bamboo tomato stake into it, then it's too dense.

Since you want to make your soil heavier, and don't trust your own garden soil, I'd suggest buying commercially-produced topsoil and adding it to your existing soil, but without the additional sand.

The risk in all of this is that the topsoil producer errs in his mix and you get a batch that is out of balance one way or another. Nothing is foolproof. -- Griff




----- Original Message ----- From: <ChatOWhitehall@aol.com>
To: <iris@hort.net>
Sent: Tuesday, May 09, 2006 9:07 AM
Subject: [iris] CULT: Raised Bed Soil Too Light


Greetings.

I'd like to make the soil, so called, in the raised bed where I grow my
bearded irises more heavy. It is already mostly organic matter, and I have an
idea it is too light. There is no natural soil in it, and that was the idea
since my garden soil has a lot of southern blight in it.

One end of the bed has more sand and that remains more moist, with the usual
problems, and when it is dry it is really light, so I know sand is not the
solution. I always add alfalfa when I turn the bed over, but that does not
heavy things up much long term.

I was considering pea gravel. I just want the plants to have something to
get their roots down into that gives more support. Fertilizer and so forth I
can handle from above but some of the plants are not as well anchored as I
would like.

I was thinking about some fresh clay cat litter. I use the regular clay ph
5.5 stuff --non-clumping--as one ingredient in my mix for rooting cuttings of
this and that--one third each litter, vermiculite, potting soil--a formula I
got from Art Tucker--- but this is one of those situations where I'd hate to
be wrong. Cutting mix is supposed to hold water, of course.

What is the deal on mushroom compost? Did not Bill Smoot say something here
about ten years ago about mushroom compost being too rich for the bearded
stuff? I suppose I should go to the archives and putter about, search term
"mushroom."

Anyone got any bright ideas?

Thanks.

Cordially,

Anner Whitehead
Richmond VA USA USDA Zone 7

---------------------------------------------------------------------
To sign-off this list, send email to majordomo@hort.net with the
message text UNSUBSCRIBE IRIS



--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.392 / Virus Database: 268.5.5/334 - Release Date: 5/8/2006
---------------------------------------------------------------------
To sign-off this list, send email to majordomo@hort.net with the
message text UNSUBSCRIBE IRIS
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index