Fertilizing rocky soil where it's half soil half stones (and no dirt)

[Cindy Hamilton]

Well, it's not what I would call a prime growing medium for plants.

It definitely is.

I just googled "compost near me" and got some reasonable hits. I live in the lush environs of southeast Michigan. Our municipalities collect yard waste (which is illegal to dump in landfills here), compost it, and sell it back at a reasonable price.

It's hard to tell from a picture. I'd definitely try the county extension service.

You certainly should be able to see stuff that clearly used to be plant matter: leaves, twigs, and random partially rotted dross. Evidence of insects is also good. If worms don't find it congenial, then plants won't, either.

Amending soil with organic matter involves rounding up a bunch of composted plant parts and mixing it in. Gardening in containers is tough (harder than Mark Watney made it sound), which is why I suggested buying potting mix. Too much water, and plants die. Too little water, and plants die. The organic matter acts like a big sponge, and is loaded with soil bacteria.

I've got pretty poor soil; a couple of inches of topsoil over 12 feet of clay (not the caliche of the Southwest, but still pretty heavy). Every year I plant a few dozen heads of garlic. I've got two frames that I made from untreated cedar fence pickets, so they're about 3 ft by 6 ft by 6 inches. I plop them down in the garden, fill them with topsoil and compost that I bought in big bags from Home Despot, use a garden fork to mix it with what was left from last year, and poke in the cloves of garlic.

Sorry, I'm getting a little "stream of consciousness" on you. It just occurred to me that if there wasn't already anything growing in your soil, it's very unsuited to your purpose. It'll take a whale of a lot of amendment to get it to grow heavy feeders like vegetables.

Best of luck.

[Dean Hoffman]

Some cut.

Here is a list of land grant universities:

They were set up to help farmers but one near you might have other information. This is to the University of Nebraska:

It does have some stuff on gardening.

[Danny D.]

Do you think it's a good idea to "loam" the soil by mixing in some uniformly sized sand grains?

I was wondering if I could grow a horse radish for myself from the condiments I have in my refrigerator! :)

[Danny D.]

Thanks for teh pointers. I found this "LIST OF LABORATORIES FOR TISSUE/SOIL/WATER - AGRICULTURAL ANALYSIS".

The only one that is close is Eurofins STA Laboratories ?V

7240 Holsclaw Rd Gilroy, CA 95020 408-846-9964 F 408-846-9954 Grapevine disease testing & diagnostics, seed (health, analysis, & purity), & resistance screening

I called them, and they said they only analyze grapevines. So they gave me the Demoines main number 515-265-1461 to ask for more detail.

They also said UC Davis seems to do a lot of grape-soil testing, even though the wikipedia you gave me only lists UC Berkeley.

So, it seems, out here, they are mostly focused on vineyards.

[Danny D.]

Do you think this soil is "loamy"? To me, loamy means loose and airy. It seems clumpy to me.

Interesting. Darker? This is coffee colored. The classic rock out here is red chert. It's really mud from the ocean. It's only about 30 million years old, which is relatively young stuff (as geology goes).

Hmmm... what does the extra foot in the air get you? Why raise the beds?

I'm up in the Santa Cruz area, so maybe the Santa Cruz UC will have that. I'll check.

They seem to have good contact information:

Heck, they even have a "Household Archeology Lab"!

[Danny D.]

Did you see my lawn in the background? I would tend to agree with you! :)

You guys probably get rain, right? We don't get rain. Not a drop. At least from about the end of April to the middle of November. Not a single drop.

I'll try but I'm in a county that doesn't have farms all that much. At least I've never seen a farm. Some leftover orchards though. And lots of vinyards.

No bugs whatsoever. Not a single worm in four buckets of raw soil. No plants either. A few scattered roots though.

I looked up what plants need. They need a complex mix of stuff, only some of which is NPK. Sigh. It's not so easy. Maybe I'll just grind up some leftover food in a blender and mix *that* into the two 5-gallon buckets.

Hey, Can the kids plant these?

Will that old garlic grow?

I buy the big bag from Costco - and always have this much wasted.

[Danny D.]

Out here, in California, except in the winter, the moisture has to be pretty low.

I looked at the first in your list:

It was the DT-129 and it was just for wood (not soil).

But it's too expensive to be practical ($166). It does seem to simply be a resistance meter though.

I'll bet most of the moisture meters are resistance meters.

Looking at the second one in your list, it's half that price:

But it's a "Wheat corn paddy rice moisture meter" for testing grains. Still, it seems to be a resistance/conductance meter.

It gives a range of Moisture measurement range: 2%~30%

[Moe DeLoughan]

That's easy. Have a sample of the soil tested. Most universities will do it for a small fee. Contact your county's agricultural extension office and ask about getting a soil sample tested. They usually have the instructions and submission form available, plus the address to mail or drop off the sample. They may have a listing of additional places that you can send your sample to for testing, besides the university.

In general, a soil test report will report on the amount of organic matter present, indicate the type of soil, test for pH, phosphorus and potassium levels. Testing for nitrogen levels usually isn't done because nitrogen generally is not persistent in the soil. They'll recommend how much nitrogen to apply based on what you tell them you're intending to grow in it.

Or you could bypass all that and just start gardening. You could make it a science project for the kids - one bed or container with the soil as-is; another bed or container with the soil augmented with a small amount of fertilizer. You could further tweak the experiment by having a third bed, where you apply half the fertilizer at planting time, and the other half about 6-8 weeks later. Have the kids keep records as to how well the plants grow in each situation, and which produces the most of each particular vegetable.

[Danny D.]

I called the Iowa number but they only do nutrition analysis. So they suggested the universities.

I'll try UC Santa Cruz next ...

[Danny D.]

Their phone number is odd, as it either gives a busy signal, or it says it's not in service...

831-459-4089

[Danny D.]

This is along the lines that I was thinking also. Having the soil tested is good because it would be a concrete proof of whatever it is, while doing the experiment will back that up.

The closest school is UC Santa Cruz, but their soil lab number is odd in that it either displays busy or not in service: 831-459-4089

I'll look around for another number...

[trader_4]

Why don't you ask some neighbors in the area what they grow? Anyone have a garden? Any local garden centers that sell veg plants and such? That would be more useful than us telling you what we have and do in NJ. Let's put it this way, given the soil you showed us, if I was going to buy a farm to grow vegetables, I wouldn't pick your place. Any farms there? What do they grow besides rocks and agnst?

Assuming there isn't something terrible about that soil that you;ve sifted, eg it's full of salt or something, then if you want to use it, get some organic matter like peat moss, well rested manure, or similar and mix some of that in with it. That plus some fertilizer should be fine for growing typical plants. Get the PH tested, they even have cheap test kits at HD or online, correct if needed.

[Danny D.]

I know of a fifty acre plot with a garden out back, but he brought in soil.

Sure. Home Depot. OSH. Lowes. That's about all "I" know, but there must be more.

Out here? It's all vineyards. No farms.

I wonder how to *test* the organic matter content of the existing soil?

I'll look for a ph kit. I have a pool ph kit (drops). I wonder if that will work somehow.

[Danny D.]

Hmmm... I guess "cemented" soil is bad, I guess. So, from that 'sandpoint', the sandy soil may be better for drainage.

But, um, what is the problem with water. Plants need water to live.

And, they don't "drown" since they don't have lungs so they don't "breathe" either.

I guess if the roots are very wet for a long time, they may get diluted of their ATP and other chemicals necessary for life, by osmosis into the water.

Is that what the danger is of too-wet soil? And how do you know it's too wet?

So many questions, so much I don't know.

[trader_4]

You can use the pool kit. Just put a tablespoon or two of soil into about

1/4 cup of water. Mix it up, then let it settle for a few hours or overnight. Carefully collect some of the clearest water at the top to fill your pool test tube. It's a little harder to read the color because the water probably will be cloudy, not clear, but you can get a good idea of what the PH is. You want around 6.5 to 7 for most things. You can look up what specific plants like.

[gfretwell]

Did we hear where this was? (I am not following it that closely) I know in Maryland south of DC, the "dirt" is pretty much concrete without the portland. It is a mix of round stones grading all the way down through sand to silty clay. When my father wanted a garden, he dug out about a foot of this "bank run gravel" sifted out the stones and replaced them with a mixture of peat moss and cow manure to get a foot of "soil". He grew all sorts of stuff successfully. I good friend of mine came from a family that made their fortune digging up large tracts, grading it into concrete aggregate and selling it. He was left with large tracts of quicksand that would harden into clay and useless to everyone. Then he got the contract from the DC sewer plant to haul away the sludge., They mixed it with the clay and after it aged a while, they had the best top soil around. Unfortunately, tomato seeds survived the while trip and people had wild tomatoes coming up in their yard.

[Dean Hoffman]

Look up compacted soil or soil compaction.

More reading:

[Ricky]

Meet Professor Kratky's easy/cheap hydroponics system:

[rbowman]

There are inexpensive soil testing kits that will give you some idea of what minerals, if any, are present, and the alkalinity. What are you trying to grow? Different plants prefer different profiles and soil types.

[rbowman]

This is the one I use. It's a science experiment in itself as you collect and prepare the samples, mix them with reagents, and compare the results fro color or density.