This is what I am trying this year as well. It is near a water source though, so I will be able to water daily if needed. Try it and see, or dig it out and refill....about the only options.

Try mixing in some new vermiculite and peat every couple of seasons if you find you're having problems

As the compost breaks down more and more, it takes on more water retention and percolation properties. Plus, vermiculite doesn't really break down, so uprooting old plants will help bring some back up to the surface.

Everything I've read and from my own experience, vermiculite does break down. Wet, it is mushy, dry it becomes 1/2 or less the size in a year.
~tom

it's not so much that the vermiculite breaks down as it compacts back down into it's raw mica form. When mica is heated in a blast furnace it puffs up like an accordion - which gives it it's amazing water retention ability - however under pressure it'll turn back into a little stone pellets again.

Take a large piece of vermiculite and squeeze it tightly between your fingers and you'll quickly see what I mean...

The vermiculite seems to stay in better shape, longer, when it's actually in the Mel's Mix. (I've just been troweling some fresh compost and a little more vermiculite into mine, but when I first troweled some of it up I was surprised at how well the vermiculite seemed to have held up in my mix.)

does everyone use compost, because last year i used potting mix in my boxes and everything did ok. i had a hard time finding four or five different kinds of compost

I went down to the local garden supply place a few days ago ready to buy bags of vermiculite, peat moss, compost, etc, enough for the five 4X8X10" beds I just made (nearly a cubic yard worth of mix for each one).

The manager there, who's been in the business forever, convinced me not to spend the three hundred bucks or so at his very own establishment and said just to get municipal compost. I had considered that option previously, and when he recommended it, I just couldn't refuse saving myself a couple hundred bucks.

His opinion was that 100% compost worked great, held moisture adequately, and since it would be amended year after year with fresh compost, it would eventually become compost anyway. All the planting beds around his business were done with 100% municipal compost.

I have made Mel's mix in the past for my beds, and it has worked well. But, later this week, I'll be getting 6 cubic yards of compost, and at $17/yd, it's about 1/5 the cost of mixing your own soil. What can I say, I'm cheap!

We'll see how it grows!

Is there a problem with using municipal compost in vegetable beds? I know in the Austin (Texas) area, the Dillo Dirt is not recommended for use in edible beds...

The only problem with city compost is that it's not very diverse in the micro-nutrients you'd find from quality compost - unless you consider broken glass, plastic, cigarette butts and the occasional piece of still-potent poison ivy/oak/sumac micro-nutrients in which case it will be very rich in those materials.

LOL, If you do use city compost, add a couple other composted materials in it to add diversity to the blend... or go poking around the "Farm & Garden" section of your local craigslist and look for people selling compost there. In my area there are always people looking to get rid of their composted horse-stable cleanings and even a couple organic farmers looking to get rid of their stuff.

If you have a Monterey Mushroom factory near you, that would probably be the best source of compost (used mushroom substrate) ... at least in my humble opinion.

Another thing to consider is the material you introduce in the rootballs of any seedlings you plant. Most seedling or potting mixes will be mostly peat and perlite. It's not a huge amount, but I think it's a noticeable proportion per square.

the most harmful thing in municipal compost is the petroleum based things-oil, paint, paint cans, etc....

The city I live in claims that their compost is "certified" by the US Composting Council, which I never heard of before: http://www.compostingcouncil.org/section.cfm?id=39

I'm curious as to what the actual measured results are on the city compost.

Has anyone had success in using city compost -- I would like to do this (city compost only).

we used the compost from the municipal recycling center one year with terrible results. Was far too woody & we're now convinced it had some sort of herbicide in it. We kept amending the beds with little to show for it.

On the other hand, as I have posted a couple of times, we now get compost-able material from a local coffee shop/cafe, which we throw directly into our beds along with quail manure & other stuff. The other stuff includes peat moss, vermiculite, straw, leaves (often snag some of the yard waste bags people fill from their yards), etc. The material from the coffee shop is coffee grounds, veggie scraps, egg shells, etc. We just turn these things in with a shovel. The first year the beds performed well, but this is the second year & so far things are down-right lush. We're thrilled because we have only sand for soil & we can't afford to purchase a lot of fill material.

The peat moss & vermiculite we added at least once to each bed, but I didn't remember to do it the second time in some beds. Still, we seem to have good retention & drainage.

So, while I think it's great to find any free material you can, if it is municipal compost I would recommend trying it out in a small area at first to see if it is good or bad. Other materials have worked well for us. Good luck!

I would caution you against using the yard waste of neighbors and city compost. Most people (at least in our area) use roundup-like products on their yards, and this gets into both their bagged yard waste, and the municipal compost. It can stunt your vegetable plants. For more details, google "Persistent Herbicides" for sad stories of various cities having this problem. It happened in my hometown (Spokane, WA) and the city actually sued Dow chemical, as they found residue of a specific dow product. Unfortunately, they only recovered a small part of the millions of dollars in damages.

Years ago where I lived the backyard had a pretty severe slope. My bed was 16ft wide and was level in the front and shoulder height in the back. I filled it with nothing but municipal compost and the results were amazing (except for corn)
Its a lot of work cleaning the glass, trash bag pieces, legos and all the other junk in it, but its free and back then I had more time than money so it worked out.

After over a dozen years my vermiculite and peat moss is gone. Now my soil is 100% compost. It's great but it is definitely a heavier mix and it tends to puddle up just a little bit when you give it a serious water. It does drain, but nothing like the original mix does. But everything grows in it. Come on over and browse the picture gallery on my website...www.thewealthyearth.com. It might give you some ideas

mmmmmmm, yummy, municipal compost. Composted sewage solids and all the heavy metals that go with it. Salty. But free.

you've got a point

I am trying SqFt this year, built 1 8" high bed and 2 16" high (high enough to sit and garden....) The bottom is about 2" of shredded cedar mulch and the rest is "black gold" certified organic compost. The cost for either is $30 a yard - about 1/2 the price than by the bag. I'll post later on the results. =)

If you have the space, tree services (municipal and businesses) will usually provide free mulch - shredded trees - delivered to your location. The usual catch is when the truck is full... 20+ yards of material. That is a lot of ground cover and compost fuel.... If only I had an acre or 2.