imafan26
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Re: cardboard in raised planters

Actually, I do put newspaper at the bottom of my bed to keep weeds from coming up from below at least for a short time. It does give the plants a head start. I also put a few layers of newspaper on top of the prepared soil and plant through it for the same reason. Newspaper works better than cloth weed fabric for me. It allows water through, holds down weeds and it disappears in about 3 months.

The weeds in my garden are nut sedge. Digging it out is nearly impossible but they don't compete well with dense planting and taller plants. Blocking light is the best way to control them. It takes years to starve the nuts.

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applestar
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Another good reason is that earthworms LOOOOOVVVVE cardboard. Moistened cardboard makes good bedding, they like the paper pulp and cellulose as well as the starchy adhesive used to glue the corrugated layers together. They squeeze in the corrugated tunnels and use them as bedding in more ways than one :wink:

imafan26
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That too. Newspaper and cardboard have a 560:1 C:N ratio. A little goes a long way.

imafan26
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Cardboard also works well on the surface when you are planting. Some things sprout better in the dark or need protection. I can use smaller pieces of cardboard, newspaper, or paper towels when I am starting seeds of onions, and carrots. It helps to keep the seedlings moist and if I water them with my hose, I end up digging them out. So the cardboard protects them from me.

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Gary350
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Last Oct I put cardboard in the onion bed to keep out weeds. I covered cardboard with 2" of mulch. March 1st there were no weeds in the onion bed. It took me 30 minutes to plant 350 onion sets. I was planning to remove cardboard before planting onions but when I searched for cardboard it was gone.
Onion bed is not a raised bed, it is the same level as the whole garden. Bed has wooden boards on all 4 sides to hold in water like a levee or dam.

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Ruffsta
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Personally, I use "Mel's Mix" specifically for my raised bed and containers and seed starting - (tho I do NOT use compost for seed starting.. just equal parts of peat moss and vermiculite).. I don NOT fill my beds with anything but pure Mel's Mix.. Expensive? that depends on your budget.. but yes, when first starting off it can be.. but you can always reuse/renew and add to it as you go... just make sure to add some compost every 3mo or so to renew it.. and screen it out and add compost to renew old soil for future uses..

1 part compost - (I personally use "Black Kow")
1 part Vermiculite - (moisture retention)
1/2 part Perlite - (soil aeration - TOTALLY OPTIONAL... NOT NEEDED)
1 part Peat Moss

Perlite and Vermiculite are 2 different things and have 2 totally different uses and are not interchangeable.. ref: (https://www.youtube.com/watch?v=E4J2L0Hi_fk)

I fill my bed with equal parts using a 5gal bucket of each.. not by weight. I layer the bottom of my bed with a double folded weed barrier and that's it..

You can add other amendments like worm castings and such as you see fit for your garden bed.. but as far as newspapers, old leaves, branches and all that junk to help fill the bed up and save money filling it - I do NOT do that anymore and never will again.. I tried that once before and it totally screwed up my raised bed with all these odd unknown roots and such attacking my tomato and pea/bean plants - I was very pissed so I learned a better way and I'm sticking to it as it as worked beautifully for me.

My advice is just double up on a weed barrier cover on the bottom.. as far as worms go.. you can add them in if you want.. I haven't seen a need to with my bed atm - the plants do well as is with the Mel's Mix and fertilizer.

imafan26
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Mel's Mix is a good formula for raised beds and containers. I have a hard time finding vermiculite here and when I could find it, it holds more water than perlite and I did not need that so I just do peatlite. If you live in a drier climate or you don't water daily, adding vermiculite will retain more water.

I only add a handful of vermicast to a 5 gallon container of peat lite. Too much compost has always caused problems but other people do have success using composts in containers.

PaulF
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We don't put a weed barrier down in the raised beds since weeding the small spaces is pretty easy, but in the regular garden the mulching program is layers of newsprint covered by a thick layer of weed free straw. Cardboard would most likely work but by season's end would it be broken down enough to till into the soil for additional organic matter like the newspaper does. I have a very good source for end rolls of newspaper and will not run out as long as I can garden so I won't be changing over for a while.

imafan26
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Location: Hawaii, zone 12a 587 ft elev.

I use newspaper as a weed barrier. I also use inter planting and intensive gardening to minimize bare areas in the garden. Cardboard has been used in the past when I revewed my garden annually.

I have a section of the main garden that has nematodes. Cardboard is useful in that section to slow the spread of the nematodes.



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