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Project Ideas: Garden Club

raised garden bed size


The title of this post should be, to fill or not to fill that is the question. I have a need to raise my current raised garden bed to a much higher level due to health reasons.

The new garden area will look like a wide and flattened U 12’ x 8’ with a 4’ notch in the center for easy access.

I am planning on using 2X12’s stacked 3 high for a total 33 ¾ inches.

Now the questions:

1, use treated lumber or use rough cut from a local saw mill

2, should I fill it first with some crushed stone or pea gravel

3, do I line it with landscaping fabric

4, will I need to drill some drain holes

5, how many yards of soil will I need, I have trouble doing the difference from Ton to yardage, a rough tonnage in my mind would be close to 8t.


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Posted 2016-03-20T00:52:38+0000  by Bigpat Bigpat
Hey Bigpat.

After giving it a lot of thought, here is what I have come up with.

Pressure treated lumber will last longer than rough cut lumber but you will have to line the inside of pressure treated lumber with weed block fabric due to the fact that pressure treated lumber is treated with formaldehyde.

Because you are going to need 8 yards of dirt to fill this box, and the first bottom foot of the planter is less important due to the fact that the crops roots wont really reach it. You could put rock in the bottom 6 inches or so to help it drain but otherwise the water will leach out between the boards just fine. You do not really need to drill drain holes.

The problems that I see about 1 year down the road is that 2X12's if not reinforced every 2 to 3 feet with sturdy stakes, will bow and warp to the weight of the dirt after a short period of time. You are going to invest a little bit of money in a good quality dirt so the last thing you need is to be replacing boards. If it were I doing this, I would consider using 4X6 timbers instead. They would not require reinforcement stakes. They could be stacked  in a brick wall pattern and nailed together. This bed would last well over 10 years and require little maintenance.

If you have good healthy soil that is conducive to growing crops then I would recommend using it and amending it with some composted manure. If your soil is like our clay here in Georgia then I would recommend amending it with manure, soil conditioner and peat moss.

Put a little more investment in your lumber and it will save you a lot of heart ache and hassle down the road.

Posted 2016-03-20T12:43:23+0000  by Ingar_HD_ATL
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