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smord

Why not amend soil?

smord
14 years ago

Hi! I've been reading through this forum as I plan for landscaping my backyard in the spring. I've noticed many comments about NOT amending soil before planting trees.

My question is - why? Specifically - what is the harm and how can I avoid those harms when I need to add something just to have enough soil? (And why do the recommendations seem to be different for perennials?) When I planted bushes in front this year, I added organic garden center soil to the back fill, and keep going out to add soil as the soil settles (trying to make sure the roots are close enough to the surface, of course). We'll see how they survive the winter.

Here is my situation: I'm in a newly built house that started with no landscaping, a lot of fill dirt from who-knows-where, and a lot of compacting. I also have no extra dirt I can move from one place to another.

In the spring, I plan to till the entire backyard under, largely to get a smooth surface, remove the nails, etc so I can have a comfy lawn for my toddler to play on.

I figured I would do that right up to the property lines where I plan to plant ferns, shrubs, small trees, and perennials around the perimeter (I'll be asking lots of tree selection advice in the future...)

We figured we'd add a bunch of extra soil of some sort from a garden center or compost from a recycling center while we till under the grass and clover (and weeds weeds weeds)

Should I not till around the edges where I will be planting trees? What should I use to add to the backfill to make sure I have enough soil when I plant the trees so the tree isn't sunk into the ground when the soil settles?

Thanks!

-Sarah

Comments (31)

  • Embothrium
    14 years ago

    Have a look at this, you might get something out of one or two of the discussions linked to here. They are all pdf format so you have to be able to look at those.

    Here is a link that might be useful: Horticultural Myths

  • ken_adrian Adrian MI cold Z5
    14 years ago

    ok... welcome.. newbie ...

    it is said.. God knows by who ... lol .. that a tree is twice as big underground.. as above...

    so picture that 80 foot oak tree ... and tell me why amending a planting hole is going to do anything .. in the long run ... for that tree ... ergo ... its a waste of money ...

    when you amend a hole.. and create SIGNIFICANTLY divergent soil types... SOMETIMES a plant.. will NOT grow out of the hole ... its just too nice in there ... leading to future failure .... this is significant especially when you are dealing with 2 extremes.. such as hard clay soil.. and a soft back fill soil ... trust me.. i learned that with yellow sand and peat-based media potted hosta.. to the tune of 120 lost plants

    this goes for trees, conifers and shrubs .... they just dont need anything but PROPER PLANTING... and PROPER WATERING for the FIRST 2 YEARS .. and we can cover all that some other time ...

    you are talking apples and oranges when you expand the discussion to annuals and perennials ... the rules all change because they have differing water and food requirements ...

    in theory .. after the second year.. the trees et al .. should NEVER need anything ever again ... they dont need food.. nor water.. nor anything ...

    fast growing flower producing plants.. need a lot more water on nearly a daily basis... as such.. an amended BED [not hole] can decrease the number of times per week you need to water .... but that discussion is for other forums ....

    so.. in summation.. IMHO:

    its a waste of money
    its not necessary
    and in theory, potentially counter-productive ...

    is that enough reasons???

    good luck ...

    ken

    ps: just leave out anything on your dream lists.. that claims to be fast growing ...

    fast to grow.. fast to become a problem.. fast to die ....

  • Dan _Staley (5b Sunset 2B AHS 7)
    14 years ago

    Specifically - what is the harm and how can I avoid those harms when I need to add something just to have enough soil?

    First, I can drive around Denver area and see lots of leaning trees (many of our landscape companies here need a LOT of training), due to too much OM as amendment and uneven settling.

    Second, the roots will spread farther than the planting hole, and you want them to. Giving them extra nutrition in one area keeps them in that area, when their roots should be spreading wide to find water.

    Third, there is a ton of research that finds that you shouldn't amend the soil, for the above reasons and more.

    Dan

  • coltrane
    14 years ago

    smord, how can you not have enough soil? Im puzzled.

  • smord
    Original Author
    14 years ago

    Thanks! All of that makes a lot of sense. I've been reading about perennials for 2 years but only actually gardened for one season so far, and I am completely new to the world of trees.

    Question: What is "OM"? Organic mulch?

    Since I also want to plant shrubs, perennials, and grass in a mixed border along with the small flowering trees, is there significant danger to just tilling the whole area in the same way? It won't need to support a large tree(property is too small). If I just plant small dogwoods and redbuds, will they suffer significantly from the treatment I'm giving my perennials? In general I do try hard to pick perennials that are well adapted to the site, so while I amend the the bed with top soil before planting, and till the compacted soil, I'm hoping to not have to add much else or do much extra watering. (Didn't need to water my border in the front yard at all this season...then again, it was a REALLY wet summer.)

    Or can I really only have healthy trees OR healthy perennials OR a healthy lawn in a site that has been altered from its natural state by the construction? (If it has been left as it was, I'm sure all native plants would do just fine.)

    Thanks
    -Sarah

  • smord
    Original Author
    14 years ago

    Hi - the issue with "not enough soil": I'm finding that when I dig to plant, the soil settles a little lower than it was before, creating a a place for a puddle to form around the crown of the plant. So to avoid that, I add purchased soil or compost from the recycling center to the backfill. (I'm also learning to put woody shrubs on a little pile of dirt so they don't sink...) Then I keep adding soil as the soil gets washed away above the roots - we're on a slope. Definitely open to any suggestions here!

    Also, we have a LOT of rocks so when I dig out the rocks I need to fill the holes.

    I don't want to take dirt from another part of the property because the property is small and I don't want a hole anywhere. Plus I use any extra dirt to keep water from seitting around the foundation when it can seep into the basement...

    -Sarah

  • sbeuerlein
    14 years ago

    Hi Sarah,

    Putting the wrong trees in heavy, compacted, contractor-grade subsoil will not result in success. No, not every soil has everything that every tree will ever need.

    All plants benefit from a healthy, porous, living, uncompacted topsoil, even trees. Especially dogwoods! Tilling organic matter over a large area is beneficial to the soil and any plants trying to grow in it. I wouldn't hesitate to create your good garden beds for your annuals, perennials, and, yes, your dogwood.

    The key is to create a rich topsoil which blends from the porous, organic top tier to the heavier lower levels without creating what they call a bathtub and without making a soil interface. A bathtub happens when you dig a big hole for a tree, dump a bunch of organic matter into it, and plant the tree in that. The two different soils--the orignal hole now forming a basin and the amended fill material--hold water differently. Basically, the "bathtub" fills with water quickly and drains slowly, so you have a condition where your tree roots tend to remain in that original hole and, often, rot.

    An interface is where two very different soils meet. Think of a coffee filter full of grounds as a strata of soil. The grounds in the filter need to be fully saturated before anything drips into the pot. Likewise, a heavily amended soil of very different texture on top of a subsoil needs to be fully saturated before water moves downward into the lower soil. This can create a lot of issues with water and air availability in the soil and where roots can't properly function.

    If you are careful not to create an interface as you add organic matter, and this is tricky with a tiller, you can really improve your soil and the health of your plants. Try to limit the amount of organic matter that gets into the soil, say 6-8", and add a bit more as you work your way up.

    The idea amount of organic matter in a soil is about 5%, so you don't need to go crazy with it. With that amount, you are adding fertility, you are creating an environment healthy for microflora, and you are improving soil structure. Soil structure (basically the amount of pore space in soil) is improved in heavy soil by organic matter because it binds small particles together, creating larger particles and thus more pore space.

    Once you've done all this work, mulch the area and try to walk on it as little as possible. Because organic matter is consumed over time, additional organic matter in the form of mulch or compost can be top dressed in future years. Over time, this very effectively improves soil.

    Scott

  • Toronado3800 Zone 6 St Louis
    14 years ago

    Smord, my friends who have bought new neighborhood homes do have more difficulty getting plants to grow in the compacted dirt they're left with.

    I've seen pictures of Ken's landscape, its nice so I know he's right for yards like his and mine which (I'm guessing in his case) haven't had the top soil sold off by the developer just a few years previously.

    When I plant even in my yard I sometimes loose a little original dirt as part of the weeding process. GENERALLY if I'm planting potted trees or those with a rootball I have enough to fill in properly. If I'm doing the small bare root fellas I need to backfill just a little. I do this with the CHEAPEST unfertilized top soil available from the box stores. I seem to do ok survival percentage wise.

    sbeuerlein has a point about the compacted nutrient poor subsoil left in some new neighborhoods. I suspect there is a cheap way of testing your soil to see what's missing so you're not just guessing what needs added. Still I wouldn't go crazy with the fertilizer.

  • lou_spicewood_tx
    14 years ago

    {{gwi:79083}}

    I live on limestone rubbles and I didn't till it at all. That is SUBSOIL. What I did was focus on improving soil biology by using organic fertilizer few times a year. Works better, a lot easier and cheaper to use compared to compost. I decided to speed up earthworm repopulate growth by adding some to the mulch on every tree and plant beds. Turned out to be a great idea. They're everywhere. I planted a tree in my next door neighbor's backyard which is only 15 feet from my yard and I never saw a single earthworm and the soil was very compacted. Anyway, the upper 8-12 inches in my ground is black fluffy soil filled with tons of earthworms. That's after 3 1/2 years. I did add a lot of greensand, zeolite, lava sand, etc to add trace nutrients on top of the ground and let earthworms take them in to the soil deep down. Trees, lawn, etc thrived. A lot of neighbors asked me how I did it and how much I water it. Every single of them was surprised to hear that I water deeply only if needed, every 7-21 days during hot summer while they water lightly 3 times a week.

    You may want to look into Plant Success and Biozome to speed up the soil improvement process if it's that bad. I just bought Biozome to try it out and see what happens. Cheap so it can't hurt to try.

    Whenever I plant a tree, I dig a really wide hole (around 6 ft wide) to get rid of large rocks (over 6 inches) and just basically loosen soil in that hole but keep sides roughed up, not smoothed. Occasionally, I had to buy some bagged top soil if I dig out a lot of large rocks that were in the way. I backfill original soil first then bagged topsoil on it till they are several inches above ground. They eventually will settle to the ground level. I sprinkled plant success on the rootball of the tree since my ground is in terrible shape and want to speed that up. Once I finished planting and mulched on the entire hole, I used a solution of fish hydrolyzed fertilizer, seaweed liquid, molasses and humic acid directly into the root ball. That will really get soil biology going to improve the soil around it. I'm going to start using biozome to see if it'd help with soil compaction deeper into the ground. Seems that I get only 8-12 inches of good stuff before hitting very compacted soil and still white. Biozome is supposed to improve soil compaction deep down with very little oxygen needed so I figured why not try it.

    Here is a link that might be useful: Soil Food Web

  • gardengal48 (PNW Z8/9)
    14 years ago

    Scott is right on the money :-) The advice is to avoid amending individual planting holes as this is where the bathtub effect and soil interface issues really come into play. If you need to amend - and LOTS of new construction homes (& many older properties as well) have soils that would benefit from amending - amend as large an area as you can manage.

    Depending on where you are located, bulk soil providers may offer garden soil mixes that would be appropriate for your needs. These will typically have a reasonable percentage of some sort of organic matter (OM) but not too much. You can either make mounded planting beds out of this soil or incorporate it into the existing soil throughout the area you intend to plant. This is far easier and far less expensive than buying an assortment of amendments that may or may not be necessary.

    Fertilizers are NOT amendments so don't get caught up in that confusion. If one takes the time to improve the soil correctly before any planting is done, very little fertilizing will be necessary going forward.

  • ken_adrian Adrian MI cold Z5
    14 years ago

    it is very easy to get NATIVE soil ...

    dig a hole somewhere else on the property .... and use it ... and its free ...

    E.g. .... build a sand pit for kiddo.. and use the soil elsewhere ...

    answer this though .... lets say you till a 5 foot wide.. 100 foot bed on the property line... are you going to spend $1000 on mulch .... are you going to just let it go back to weeds ...

    my point... is that i THINK.. you might be jumping into the deep end....

    lets be realistic ... you have the babe .... IF you are lucky you will have an hour or two per day ... it would be very easy to plant a plant.. here or there ... or start developing a small annual/perennial bed ....

    but it sounds like you think you are going to landscape an entire yard in one fell swoop ....

    perhaps if there is a budget to hire a truckload of young burly men....

    but .. and i say this as a stay at home dad ... you are going to be hard pressed to put into action.. what you have already stated ... on your own.. with even the most complacent child ...

    below is a picture .... there was barely any plan for the beds ....

    dig hole in pure yellow sand.. which is barely a 'soil' .. remove plant from pot ... unwind or do surgery on roots ... insert plant... add mulch ring at least 1 to 2 feet around plant .... and water PROPERLY for 2 years .... when you have a nice group of plants... increase mulch until the bed takes some shape ... no second person.. no heavy machinery ... and you too can have that in about 10 years ... that is how long i have been here ...

    {{gwi:492318}}

    good luck

    ken

  • sbeuerlein
    14 years ago

    So the sand is yellow. It still drains. It still has pore space and allows for gaseous exchange. This is not the case with compacted clay. But either way, sand or clay, organic matter is beneficial. I've never heard anyone argue against the value of a good, rich topsoil.

    Sarah, if you want a fully landscaped yard, you can have it whether you have a baby or not. Granted,a truckload of burly men would be helpful, but they are available and sometimes worth the money. They can be found in the Yellow Pages under landscape companies.

    Doing the job right in the beginning by creating a good soil will make it easier every step of the way. And a nice raised bed with decent topsoil, which drains well but accepts moisture readily, will make PROPER watering almost fool proof.

    I've made gardens both ways. When the budget allows (usually for clients) properly improved beds. When not (usually for myself), planting in normal suburban soil and trying my best to keep things properly watered and improving the soil the best I can over time. Believe me, there's no comparison!

    Regarding costs, 5' x 100' flower bed equals 500 square feet. At 2" depth, that is about 3 yards of mulch at about $20.00 a yard. $60.00 in total. Compost, composted manure, or mushroom compost costs about $30.00 a yard. A bit more but they all add a lot more nutrients than hardwood mulch can ever provide alone. If budget is a concern, mulching with leaves collected for free in the fall is an option. Sometimes free compost is available in some communities.

    Nutrient poor, lifeless, soil will grow many trees, whether it is clay or sand. Some plants simply are adapted to and perform better in extreme sites. Most garden plants, trees included, however, respond better in rich soil. No serious horticulturist will argue this. Mind you, I am NOT recommending amending of planting holes. I am talking about building topsoil.

    You can have a beautiful mixed border which includes both trees and herbaceous plants. You don't need to have your perennials basking in a chocolate cake loam while your trees are banished to rock hard ground. As long as the rich topsoil transitions nicely to subsoil, basically mimicking a good, undisturbed soil, as you would find in nature (such as in a forest, where trees grow in abundance), then you'll see excellent results.

    A quick note that some of this depends on what you wish to grow. I think you mentioned dogwoods somewhere in this thread. Dogwoods are notorious for needing perfect conditions. Plant one in full sun in spare soil and it'll suffer. Conifers, on the other hand, frequently prefer a leaner soil.

    Incidentally, whoever posted that link to the soil website, thank you. That is excellent.

    Scott

  • ken_adrian Adrian MI cold Z5
    14 years ago

    yeah.. its yellow ... but i should be saying 'mineral' sand... as yellow means little.. i did learn the proper term from a soil test.. which would be a very good thing for OP to start with ... you cant get much more benign that that .... here is a pic
    {{gwi:234645}}

    and here is the hole that i steal native soil from for other projects ... got a very pasty freckled red head.. he gets a shade structure.. the hosta are on their own.. lol.... the kids love their MUD PIT .... talk about drainage ... they can run the hose.. for nearly 3 hours.. before a puddle of any size will develop ...

    {{gwi:250981}}

    and here is that first warmish day in spring.. when I WON ... took it all out of him.. i asked what happened when he later awoke.. and he said the blacktop was just so toasty.. that he sat down.. then lay .. then that was the end of that ... lol
    {{gwi:492321}}

    ken

  • smord
    Original Author
    14 years ago

    Wow! This is terrific- you guys are awesome. I'm certainly getting much better advice than from most of the landscapers I've talked to around here.

    It sounds like I may have some good news- I do seem to have a lot of earthworms, so the soil must not be THAT compacted. And Scott, what you were saying about not creating an interface makes a lot of sense- I'll be careful with that.

    I should make the effort to collect soil samples an send them to my local extension for analysis before amending too much.

    Ken- you are right about not takin on too much. Many onmy questions are really directed at a 10- year plan. Last season, after putting significant ecfor into preparing a bed ( maybe 8x30 feet) by turning over the soil with a shovel, I was able to put together a very satisfying perennial border in a season Which I hope will only improve with time.

    So this time I plan to put th bulk of the time and effort into preparing the backyard soil (we have a burlyfriend with a tiller who has offered his services in exchange for beer and conversation) and seed the grass. I want to have a longterm strategy for the borders, but I will probably only plant a few trees and shrubs ( all babies) to get them started establishing themselves. I might mulch the to- be borders, or I might just put grass there for now

    I do have access to free mulch from the recycling center. The downside is that it is unscreened, but I kind of enjoy weeding and I'm not looking for a golf course lawn anyway.

    It sounds like I might want to rethink the dogwoods.... Another reason is that bears love the fruit and we have a serious bear problem here ( or rather the bears have a serious human problem). I might want to wait on final seection of trees until I find out what's in my soil.

    Thanks!
    -Sarah

  • smord
    Original Author
    14 years ago

    Also thanks for the explanation about a planting bathtub. That's exactly what must have been happening when I planted my few shrubs- they were not in the pre-prepared bed, and were right next to the foundation where the compaction must have been the worst. I would dig holes and add organic top soil, but they kept sinking after planting. I kind of semi- dug them up again to puthem on more soil and dug little moats around them for the water to drain.... Would have been easier justto prepare the whole bed! Now I know what was going on. We'll see how they survive the winter. Fortunately I picked species that can handle wet....

    -Sarah

  • ken_adrian Adrian MI cold Z5
    14 years ago

    planting potted stock is a lot more than tipping it out of the pot.. and sticking it in the hole ... we have referenced the issue of diverse soil types.. and potting MEDIA is very divergent from your soil as described ...

    did you break up the root mass???

    did you plant at the proper planting time???

    did you plant properly ...

    you will also need to learn how to deal with mail order ...

    so much to learn .... so little time

    ken

  • sbeuerlein
    14 years ago

    I try to make my container plants as "bare root" as I can make them when I plant, knocking or washing the media off the best I can. Don't have many issues at all with a correct planting time for container plants. That's one of the great conveniences of them. However, late summer planting is tricky because it's usually so hot and dry, this year excepted.

    Planting depth is important.

    One of the nice things about a good rich topsoil is that the texture of it versus container media is usually not so different. I'm a little less anal about getting a plant's roots out of the media and into the actual soil when the bed is nicely worked up (but still somewhat anal).

    Scott

  • lou_spicewood_tx
    14 years ago

    Another good website to learn about soil biology when it comes to soil building.

    Here is a link that might be useful: Soil Foodweb

  • smord
    Original Author
    14 years ago

    Yes, Ken I did in fact know enough to spread out the roots when planting- I pretty much just treated them as perennials but dug especially wide holes so the roots would have good soil to grow into. What I didn't know about was the difference in soil textures. They were container mothers day gifts, which is right around our frost free date, and it was a nice cool, wet summer and they seemed like they were doing well all summer. It's just the potential for pooling water and eroding soil I worry about over the winter.

    What is the optimal planting time? I assumed spring or early fall so the plant can establish root systems before the heat of summer or hard frost...
    -Sarah

  • ken_adrian Adrian MI cold Z5
    14 years ago

    IMHO.. trees.. conifers... and shrubs.. are planted just after soil thaw .... in my zone 5... mid april ... giving them 6 to 8 weeks before the heat of summer .... though not much is available locally at this time.. mail order can be done so ... in my sand.. i NEVER plant in july and august ...

    or in october.. 6 to 8 weeks before soil freeze ... so summer mail order is potted and held until proper planting time ...

    it is also imperative.. with mail order.. that they be in a state equivalent to local conditions ... meaning... dont order in stock from z8.. and slam it into near frozen soil in 5 or 6 ... you hold them .. harden them off .. etc...

    ken

  • iforgotitsonevermind
    14 years ago

    Since you're starting from scratch, you're never going to get a better opportunity to have some gardening soil hauled in from a landscape material yard. Spread evenly to about 4" should do for the lawn. The time to do this is before anything is planted. It shouldn't be terribly expensive to do it. A lot of work though. Best to hire someone that has the equipment to spread and level it.

  • katrina1
    14 years ago

    Sarah,

    Did your builder leave you with compacted clay soil? If so how well draining is it. Have you dug a hole, filled it with water and timed it to see how long it takes for the water to drain out?

    I only ask those questions, because there are different types clay soils, some clays will break up in your hand when you get it wet and then take a handful and compress the handful. Other types of clays when wet will stick together and then dry nearly as hard as rock.

    If you do not have compacted sticky clay soil, is it instead a very fine silty loam soil, which has been so compacted that water simply runs off instead of filtering down through it.

    If your soil is a sticky clay, then tilling a granular gypsum, sand, and compost into it should help in addition to adding more earthworms like mentioned above.

    If you do not want to go to that much work, then it could be easier to create raised beds on top of your clay soil. These raised beds will drain properly, but could still cause you more work than anticipated, depending on how you want to edge them, and how large or many raised beds for which you would need to have good garden soil delivered.

    If your soil is compacted silty loam, than adding sand, and compost to your soil should help.

    Of course when adding what I have suggested, you still need to consider the advice given above, about not creating a bath tub situation, or about not creating a soil interface.

  • botann
    14 years ago

    I've seen people put gravel in a hole full of water and expect it to drain because the gravel is in it.

  • sbeuerlein
    14 years ago

    What Katrina is referring to with the squeeze your soil into a ball is a simple test to determine your soil texture, which is your clay to silt to sand ratio. Knowing what you've got to start with is useful. A proper soil test is important.

    Two of Katrina's suggestions I will argue with. Adding sand to clay doesn't not improve texture. The tiny clay particles simply fill in between the larger sand particles so pore space and drainage do not improve. Worse, the chemical bonds between the two basically turn your soil into something akin to concrete. Gypsum has been found to be beneficial in a very small number of soils. Do not add gypsum until a soil test has specifically shown it is needed.

    Adding organic matter, on the other hand, always improves soil structure and makes nutrients more available...up to that 5 to 10% ratio.

    There's a ton of misinformation out there. If I were you, I'd get to know your county extension agent. I've yet to meet an extension agent who isn't fully committed to a scientific approach to horticulture. In urban counties, they tend to be more knowing of suburban horticulture. In rural counties perhaps more towards agriculture. Either way, they'll be very familiar with your soils, labs for soil testing, and a host of other helpful information. The agents I've known are also extremely friendly and very helpful.

    Here's information from my State's extension service, much of which applies to any place east of the Mississippi.

    Scott

    Here is a link that might be useful: Ohioline

  • ken_adrian Adrian MI cold Z5
    14 years ago

    you have made a snowball.. yes???

    cold dry snow... will not pack into a ball.. or immediately falls apart ... that is sand .. super dupper drainage

    clay ... well you have played with clay ... rock hard .... can get wet gooey and stay that way for a week ... or until the roots rot off ... no drainage ...

    the third corner of the triangle .. see link .. silt .... somewhere in between ... will make a snowball ... but not best ...

    the key is working in organic material to get to the center known as loam .... clay loam is great.. as is sand loam ... and silt loam ...

    in fact... anything but the 3 corners is just peachy ... and why i am telling you.. that unless you are in a corner.. you probably dont need all that much ... as a base minimum.. it surely never hurts if budget.. time.. whatever is available ...

    IMHO .... trees/conifers/shrubs.. can even live in the corners ... with just a few TLC tricks.. like proper planting ...

    annuals/perennials.. and lots of other high production plants [flowers] ... need something not in the corners ... just to make your life easier ...

    roots need air as much as water.. and that is why you need drainage ...

    thats as simple as i can make it .. and gives you a base to read further.. more technical sites....

    ken

    Here is a link that might be useful: {{gwi:492316}}

  • sbeuerlein
    14 years ago

    I'd be just a tad happier if Ken changed his phrasing to SOME trees/conifers/shrubs can live in the corners. It really pays to know not only your soil but your plants' cultural requirements, which usually begins and ends (but not necessarily) where the tree grows in the wild. Right plant in the right place. That whole bit. So a flood plain species will tend to be okay in heavy, compacted clay, because they're adapted to less oxygen at the roots. Other species will be better adapted to sandy soils; a handful will only thrive in perfect loams. Seed provenance plays a part in some of this too in regards to hardiness and pH adaptability. Except for a tiny fraction of alpine and xeric species, most all will benefit from about 5% organic matter in the soil.

    Likewise, a lot of herbaceous plants actually perform better in sparer soil, just depending on what soil they've adapted to in their native ranges. I grow a lot of alpines that would never make it in my normal clay soil. I have to do a lot of work to make the lean, dry, low nutrient, gritty beds that they require.

    A soil test and a visit or talk with your extension agent is a really good place to start.

    Scott

  • ken_adrian Adrian MI cold Z5
    14 years ago

    hey scott.. i will give you that one .... sometimes i get tired of all the 'qualifications' that should be everywhere ... my statement does read as too conclusive .. for the most part.. basically ... etc ... lol ...

    but the last PP indicates my intent.. simplification for newbies ... i feel they need the 'general' idea.. before they can go to scholarly sites and understand the theory ...

    as a stay at home or someone who is just getting started ... i can grasp .. understand.. and retain a triangle ... lol ... but i have a hard time... going into the third semester of soil science ...

    here is a new way to look at it ...

    if you take the sand corner .... and dig a hole and line it with clay ... you have a pond ... all but a very few trees will not live in a pond ... no air for the roots ...

    if you go to the other corner of your triangle.. and dig a hole in clay ... and fill it with sand ... you will have a bog.. same as above... very few will prosper ...

    and silt ... heck.. no one with silt probably has any problems. .. lol ... so i will ignore that ...

    but coming full circle ... IF you amend ... it would be to add water retention to sand ... or drainage to clay [and air] ... and a LITTLE of this or that, MOSTLY likely will never be a problem .... as long as you have some idea of what you are trying to accomplish by doing such ...

    just doing it.. because they are your babes.. and they need a comfy bed.. and to be fed ... and all the other human attributes we like to assign to our garden .... is NOT a good enough reason .. nor is.. because i saw it on TV.. or online... or in a book ...

    there has to be a REASON ... a GOAL ... and if thought out.. WILL benefit the plant ...

    but i stand steadfast in saying they "do not need" [key word NEED] ... all the foo foo stuff.. if properly planted.. and properly watered for a year or two ...

    ken

  • smord
    Original Author
    14 years ago

    Thanks all for all the advice. I'm actually a geek who loves learning about all this stuff and I actually have been starting to read about soil chemistry etc, but it helps to have the simple side in which to place the detailed information as I get it...keeps things in perspective.

    So now here is my plan:
    -send 3 samples of dirt for 3 separate soil tests to my local extension when the snow melts so I know what my 3 different backyard zones are and what they need and what would do best there.

    -till the whole darn backyard with some amendment perhaps based on the soil tests and practicality and cost

    -seed the lawn when the time is right

    -spend the rest of this winter learning all about different trees and shrubs so that by the time I have the results of my soil tests and it's warm enough to start gardning I'll have a good idea what major architectural plants I will be planting and where I will buy them. (And start from seed a bunch of perennials I'd like to try out but don[t have the money to buy after the big plants.)

    I asked my father-in-law who lives in the same town and has a few beautiful dogwoods how he manages it - turns out he has them in raised beds and they are sitting on 5 feet of fabulous soil. He says our area is all clay.

    -Sarah

  • sbeuerlein
    14 years ago

    I'm sorry to prolong the argument, and I appreciate you simplifying things for beginners, but I still think you're being a bit too simplistic. There are so many examples of poorly selected trees suffering or failing outright to leave this completely alone.

    Red maples, as commonly as they're planted here, are often woefully chlorotic from either iron or mangnesium deficiency caused by high pH. Same with non-local-seed source pin oaks. Sadly, local sourced pin oaks are non-existant in the marketplace.

    Sourwoods, native and thick as thieves just a few counties east of me, fail with amazing speed in our clay and high pH.

    Stewartia--no one is quite sure why there are no old Stewartias in SW Ohio, but there are plenty of young ones (for a year or two).

    White Tigress maple, endangered unless it is planted in the shade.

    Katsura needs a ton of water until established.

    Franklinia is extinct in the wild for a reason. It is ungrowable!

    All the Juniperus scopulorum cultivars out there, as beautiful and tempting and (strangely) guaranteed by Home Depot to perform perfectly as they are, don't. In heavy clay, they die the slow, miserable death of an actor in a bad western.

    Kalmia, fulgettaboutit, unless your in East Coast acid soil.

    Dogwoods just need TLC.

    Daphnes, the land is filled with guys who have no idea why their daphnes up and left. You see their mournful frames wandering their gardens like ghosts.

    Granted, the easy woodies probably out number the difficult, but I really wince at the idea of really broad statements that make things a little too easy.

    Really successful gardening depends on picking appropriate plants for the site. A really rich, porous topsoil will go a long way in ensuring plant health. With all that trees must endure these days--pollution, drought, climate change, exotic insects and diseases, etc. etc. etc., it certainly doesn't hurt to try, if possible, to give them a good home in which to spread their roots.

    Scott

  • sbeuerlein
    14 years ago

    Sarah,
    We posted at the same time. I think your plan is excellent. A great resource for selecting trees or shrubs are the two Michael Dirr books. The Encyclopedia is the one with photos, probably your best place to start. Make your list of favorites and then get the manual. No pictures, but more details on cultural requirements and disease or pest issues. Both are readily available at libraries or bookstores.

    Lots of great perennials can be started from seed. Also, garden clubs, serious gardeners, and societies often have plant sales that are cheap. Spreading perennials can fill a lot of space fast. Sometimes this is good: hardy geraniums, phlox, etc., sometimes it is a horror show: Houytonia, Bishop's Weed, and more. Be careful you don't introduce any unerradicatable (sp?) invasives to your property.

    Scott

  • katrina1
    14 years ago

    I did not advise to add only sand to clay soil. Instead I suggested that if the entire back yard is being amended than the clay soil can be improved if the proper ratio amounts of compost, sand, and gypsum is used in combination to amend the clay soil; depending of course on what type of clay soil is being amended.

    Different types of clay soils drain at different rates, and also different types of clay soils have different degrees of fertility ranging from nearly completely void of fertility and high ratios of saline such as so often seen in the more alkaline white clay soils, mildly fertile clay soil that is redish orange in color, sufficiently fertile, slightly acidic clay soil that is fairly dark in color, and then there is the totally sufficating clay soil that is slimmy when wet and rock hard when dry with nearly nothing in its composition other than pure clay.