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smom40

Soil amendments: clay soil, fully planted beds

smom40
19 years ago

Can someone talk to me about this? Everything that I've been googling seems to be talking about what to do with beds BEFORE you plant...

What do you do with beds that have already been mostly planted? Beds are a bit raised to begin with. Throw some mulch on top and I can't see how in the future I could add amendments??

I could see how I could add some compost if I was removing one plant and replacing it with another..but what can I do in between to make this clay stuff better?

If someone could give me the 411 on this, I'd appreciate it.

Comments (16)

  • cantstopgardening
    19 years ago

    Earthworms.

    Natures little transportation system in a cute slimy little package. Now your job is to feed them. (Boy, what is it with me giving you homework??) Remember, nobody was tilling up the forest, or the great plains (before agriculture,) but years of organic matter being added to the top layer made it good soil.

    It's when we spend all out time raking up everything and hauling the organic matter out that the system got messed up. The worms aren't a very fast system, so you are correct, adding some compost in everytime you divide plants or have an open hole in the ground.

    Others might have some suggestions too. I'd be interested in too, as I don't till for carpal tunnel reasons.

  • terri_ks
    19 years ago

    Smom,
    I am in the same fix. I moved here(Kansas City) from out of state not knowing what the soil was like. The moving van, full of divisions from all my plants, and I arrived at the same time. The first thing I did was plant as they were already in shock from being on the van three days. I have been adding layers of compost and cotton burr, but after two growing seasons this spring I must face the harsh reality that if I want a truly glorious garden, I need to dig everything up and replant after I take care of the soil. I also think this climate is never going to produce flowers like I had in Michigan. I would also welcome any other ideas.

  • smom40
    Original Author
    19 years ago

    Okay, I understand the earthworm issue. Back at 'home' I used to add cornmeal, alfalfa and kelp to my beds..and occasionally compost when I had a hole to fill..Did just fine with the earthworm attraction issue. The beds were flat...groundlevel. No slopes.

    However, what I mean is that I have preexisting raised beds (without side support)with hardwood mulch on top. I can't imagine adding a layer of anything on top without starting to bury the plants...or having stuff roll down the side.

    So would I just throw a thin layer of stuff on top? Like what? Sprinkle what?

    I can't wait until all of that bark breaks down to do it...I'm a bit stumped.

    Do people pull up their mulch and then do it? Or.............?

  • pondwelr
    19 years ago

    There isnt a whole lot you can do for instant, big impact.
    You can, however, do small things. All requiring patience and time. Small holes between plants, filled with compost;
    starting over with smaller shrubs and amending those planting holes; pulling back the existing mulch and adding
    compost, leaves and grass clips; The list goes on.

  • smom40
    Original Author
    19 years ago

    Okay...thank you. Looks like some shrubs are going to be SP'd this spring. Something has to break this stuff up!

  • howea
    19 years ago

    Three things I do in MI in clay soil, living on a hilly lot with hardwood mulch. Does some good...
    1) buy big bags of Milorganite and use in spring and fall before a rain
    2) ditch the hardwood mulch on beds with flowers you love
    2) shred lots of leaves with lawn mower and pack on leaves topped with compost on the beds twice a year
    I have had to give up on this due to bad back in last two years, boo hoo, but for 12 years I had the BEST gardens.
    I also made compost and used in holes for every plant.

    Now I am using lots of spreading verbena and pretty grasses to keep the maintenance low.

  • leaveswave
    19 years ago

    Worms are generally bad news in a forest, at least in the unglaciated areas of the country. They are actually detrimental to the building up of organic matter in the soil.
    http://www.dnr.state.mn.us/invasives/terrestrialanimals/earthworms/index.html
    http://www.extension.umn.edu/extensionnews/2002/EarthwormsDamageTheSoils.html

    Your best best is to mulch deeply. Using plants suited to the attributes of the location can give you the lush gardens you would like.

  • david_5311
    19 years ago

    Mulching will certainly work, especially if done consistently over several years. But the best plan is to prep the bed before it is planted. You don't say how big it is, but it may well be easiest and give you the fastest results to dig out the plants in spring, add your 10-12" of good topsoil, compost, whatever you wish, then replant. I have been gardening on hardpan clay like this for 18 years, and my bed making technique has always been to make raised beds 10-20" deep on top of the clay. Yes, it takes a fair amount of material. But you can have a mature looking garden in one season by doing this. Most people who see my garden packed with mature plants cannot believe that the bed was made the fall or spring just before, usually with 2" Bluestone type starter plants.

    Spend your money and time on making great beds, and then buy tiny plants instead. It works (the old $5 hole/$1 plant approach, except you want to prep whole beds, not holes). You certainly won't be the first gardener to wish they had done better soil prep and take out all the plants to do so (heck, you can make a second good bed, move the plants from the first into it, then reprep and plant the first. Chances are the plants will have grown so much better you can take big divisions in a year to replant the first bed).

  • ddunbar
    19 years ago

    Add gypsum to your soil... it helps break up the clay and adds much needed nutrients.

    DD

  • RuthannaM
    18 years ago

    Tomatoes LIKE Gypsum!

  • CindyB_IL
    18 years ago

    Get yourself organized with the amendments available and promise you'll use them whenever there's the least opportunity. Divide everything that needs to be divided and dig up the whole clump, amend really well as far as you can reach. In the fall, after you begin to cut things back there is a lot more space down there than you imagine. Use a cultivator and break up the spaces and layer on the amendments. You'd be surprised how much impact.

    I compost what comes out of my garden and add leaves - it works better than anything to put back on. Also a heavy layer of mulch helps, too - it breaks down and over time you'll be surprised at the difference. Just don't be afraid to turn it under the soil and expect to replace it. Nature takes most of the volume out so it won't get that much bigger.

    Even if you prepare before, all of this really matters. My gardens all need it again - I've been so busy with work the last several years the gardens are neglected. They grew so wonderfully right after I did the beds and amended well. Someday I'll go back through one by one and remove a lot, amend, and replant - once in a while that kind of regeneration, even if you just do it in places - is healthy.

  • RuthannaM
    18 years ago

    I've heard that tomatoes really like Gypsum for the Calcium in them..
    RuthannaM M.G.

  • blewsey
    18 years ago

    I have a bed I made about 20 years ago when I first started and didn't even know there was such a thing as good or bad soil.As I learned ,I started putting my fruit peels and green veg leftovers in the blender and adding 1/2 cup water then pouring on top of the soil it seems to have helped enrich the bed.

  • Mary4b
    18 years ago

    My first garden was created 5 years ago...we took off the sod, amended with compost, tilled and planted and mulched. It was a nightmare. I probably needed 60 times more compost, and never could have afforded it. The following two years I hated working in the garden because it was such hard work with the clay and many plants didn't thrive. I replanted areas many times and each time I would add more compost/mulch, whatever I could get my hands on. I also added a soil conditioner that was very expensive but works like gypsum...breaks down clay. (Who knows, maybe it WAS gypsum with a bigger price tag.) It's 6 years later now and I have to tell you that the garden is just a delight to work in now. I plan to spread gypsum a couple of times each year and continue mulching the beds, but I'm sure I'll never have to do all that double-digging like I did before....just keep on piling on the stuff like everyone wrote above, and before you know it, your beds will be as you need them to be. I also highly recommend that you search out plants that LIKE clay, so that your plantings will be successful. I spent many, many dollars buying plants that needed more drainage than I had and would die...and I wondered why. Some of those plants might do ok for me now in the same garden, but I think it's important to plant things that actually LIKE the ground that they are in today. Good Luck!

  • jennymisek
    18 years ago

    Wow this has been a great thread to read. I live in Appleton WI, zone 4 and in plenty of clay! I am going to plant a garden next spring and plan on spending this year working the soil. I hope that learning from all of you will help me have a nice garden next year!

    You all have talked about composting, do you put fruit seeds in there? Such as apple cores? Cucumbers old tomatoes etc?

  • smitty2010
    14 years ago

    I live in NE, lots of clay. I understand gypsum breaks down the hard clay. Is it okay to apply after you have put down a pre emergent( Scott's Halt) for crab grass?