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Sand vs. compost

Posted by stacey3822 6 (My Page) on
Fri, Mar 13, 09 at 22:27

I know this question seems like a no brainer but...I'd like some input just the same.

In Mel's new book he states that I only need 6 inches of his mix and any thing deeper than 6 inches can be filled with sand up to the 6 inch mark and use his mix on the top.

I've been having this debate with myself...use sand as my bottom filler or use 100% compost from my local landfill. I'm thinking that the 100% compost would actually be better for my plants than the sand even though I'm going to use Mel's mix for the top 6 inches no matter what.

All my boxes are going to be 12" deep. I know that isn't necessary either but that is just my own personal little pet peeve, I like the deeper boxes.


Follow-Up Postings:

RE: Sand vs. compost

  • Posted by ck4b3d USDA 11 & Sunset 24 (My Page) on
    Fri, Mar 13, 09 at 23:05

I think the sand is a drainage & cost savings measure

RE: Sand vs. compost

I went with 16 inches of Mel's Mix with no sand, though I did do gravel under the mix for drainage. I have had NO problems with drainage, even in Seattle.

Good luck and enjoy!

RE: Sand vs. compost

Sinfonian -

16 inches of Mel's mix? Wow! Don't tell me you did that with all bagged products.... wasn't it expensive? I filled a single 4x8 last year with 8 inches and went broke doing it! I've seen your setup (I follow your blog - nice job!), and you've got quite a few boxes... how did you do it?

Personally, I'm setting up an additional 4x8 this year, with 3 2x2's for potatoes. I'm going to 12 inches deep, but unless I can get the compost for free or close to free, I'll be using sand or gravel in the bottom 4 inches as well.

RE: Sand vs. compost

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, Mar 14, 09 at 9:39

Since the particulate range of the sand is likely to be smaller than that of the soil strata, it will help with drainage if drainage is an issue (unless your RB is over clay). Perhaps more importantly, it (shallower layer) reduces the shrinkage of the soil. While it may not impact the shrinkage rate, it does impact the actual shrinkage. IOW, well-aerated soil with a large organic component that is 12" deep and has 1/3 shrinkage in the first year will shrink 4", while the same soil @ 6" deep will only shrink 2". This may or may not be significant enough a factor for it to matter to you, but I thought I would throw it out there. It is probably more significant in perennial plantings than yearly crops.


RE: Sand vs. compost

I use rough sawn oak 1" x 6" boards and just lay them on grass to start. Can make one 4x4 bed for $8. I coat the insides and bottom edges with roof cement plus where the boards join with deck screws.

I fill them with ~ $1 a bag "top soil" and cow manure...50-50. Find this at Lowes...40 lb bags.

$8 for the bed....maybe $8 for the start. The "top soil" is mostly organic matter and sand? The cow manure can have many weed seeds in it. Use a little of my own compost too.

When I see prices of $25-30 for a bag of potting mix...I start looking for my gold pan.

This mix has done real well with tomatoes and lettuce...the radishes I tried didn't do much...probably too rich for them?

RE: Sand vs. compost

I really appreciate all the inputs and encouragement from you folks.

I went with the compost because in this instance I was able to get some really nice compost from the landfill for free whereas I was going to have to pay for a dump truck load of sand to be delivered. So the bottom 6 inches of my beds are 100% compost and the top 6 inches are Mel's mix.

I am trying to follow Mel's book as close as possible and Yep, it's been expensive mostly for the vermiculite. But in theory, this will be the only time I have to put out this expense so I'm keeping my fingers crossed it all will be worth the expense and my hard work.

There is one thing I didn't follow and that is not using treated lumber. I am using 2" x 12" treated lumber but I am painting it with a sealer type white paint AND I'm putting a plastic barrier nest to the wood to keep any chemical seepage from the wood to a minimum. Also each bed has it's own drip irrigation system. This was installed to keep the garden watered on weekends when I'm at the lake fishing so I don't have to worry about it.

Last but not least...I want my garden to be pretty. So the outside of all the boxes have vines and ladybugs painted on them. I'm finished with the strawberry bed and the aspargus bed now I'm working on the veggie beds. I've been taking pictures and will share when done or close to being done.

Happy Gardening

RE: Sand vs. compost

  • Posted by alys Zone 5/6 - MO (My Page) on
    Tue, Mar 17, 09 at 15:09

Stacey, I can't wait to see picutures of your beds! I bet they are adorable with the painting on them. Good Luck!

RE: Sand vs. compost

Ooooh.'re going to make us all jealous, aren't you?



Here is a link that might be useful: Annie's Kitchen Garden

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