I found that “Mel’s Mix” 1 of equal parts by volume of vermiculite, peat moss, and a wide variety of composts, was far too “hot” to use. When I took a sample to the county Ag Center for soil testing, it was off the charts in soluble salts (a measure of soil fertility). Their testing registers a maximum of 1800 parts per million, and my samples (I took several) all came back at 1800 ppm. Anything over 500 is considered “excessive” and they hand-wrote “Toxic levels” on one of the earlier samples.
The Soluble Salts scale is as follows:
0 – 50 = poor
51 – 100 = fair
101 – 300 = good
301 – 500 = excellent
Above 500 = excessive
This is the current mixture I am using:
1 bale of peat moss, decompressed (7 cubic feet)
2 bags of vermiculite, less 0.8 bushel (7 cubic feet) 2
0.25 cubic feet yard and kitchen compost 3
1/2 bag of Black Cow compost
1/2 bag of Black Hen compost
1 bag of Mushroom compost
2 bags of Fafard 3B potting soil
This will fill an area 4′ wide by 8’6″ long by 6″ deep, or 17 cubic feet.
For my 4′ x 16′ raised bed. Bed has 2 rows of cement blocks.
Nature Life Composted Cotton Burrs Regular 3.0 cu. ft./bag 16/bags
Parboiled Rice Hulls – PBH 50 lb/bag 2/bags
Sphagnum Peat Moss 3.8 cu. ft./bag 4/bags
I broke it down my doing batches:
Below is 1 batch. It takes 8 batches to do 1 – 4′ x 16′ bed
12 Gallons of Parboiled Rice Hulls
1/2 Bag of Peat Moss
2 Bags of Cotton Burr Compost 100% Organic
I then used a 4-3-3 organic fertilizer and Azomite. This mixture is very loose and I can wiggle my hand down to the bottom of the bed, so for taters I can harvest them without killing the plant.
Your bed is very similar to what I did. The major difference is you have one more row of blocks and you capped them. I left the holes open so that I could use PVC pipes to create a support structure for some of the plants. Thanks for sharing your garden and the pics!!
Thanks so much for adding to the information!
I added the extra row of block, not for “gardening” reasons, but because I’m getting to an age where bending over is not a good plan. I’ll be 60 in a few months. We plan to live out the rest of our lives here, so this is definitely a long-term matter.
I thought about leaving places to add PVC pipe, but I’ve just been pushing it down the side of the block. It doesn’t do very well though. I’m still looking for a better solution – possibly some sort of PVC sockets fastened to the block. I just don’t know yet.
One thing that I like about my mixture is that it uses a good bit of Vermiculite. This is a mineral product and does not break down like the rest of the mixture. That means that I’ve got a soil structure that will last longer.
I’ll have to look into rice hulls and cotton burr compost. I suspect that one of the big variations in what is used in different parts of the country is simply what is available. This area (Central Florida) has a lot of greenhouses and virtually no cotton or rice being grown. I’m sure it’s available here, but the price may be steeper due to shipping costs.
Excellent point about being able to harvest potatoes without uprooting the entire plant. One disadvantage that I have found with mine though is that it is so loose that sweet potatoes do not form the usual “potatoes” but rather just grow long thick roots. They are not usable for much of anything. Another disadvantage that I’ve found is that plants tend to fall over when they get big. Even the tomato cages that I used for most plants will not hold up well in the loose growing mixture.
For my mixture the rice hulls take the place of vermiculite.
Here is some info on rice hulls:
http://www.hhydro.com/PBH-Rice-Hulls.html
http://www.riceland.com/coproducts/pbh.asp — lots of info here.
I use a pvc system that allows me to use a cattle panel which the plants grow up through and supports them. You might look at some of the pics on Len Pense’s website for some ideas. http://www.gardeningrevolution.com Look in the galleries for lots of pictures on how he sets up his tomatoes and pole beans.
I like being able to pull weeds out root and all, while sitting on the blocks, and not have to be bent over with a hoe.
You’re right – lots of good ideas at the gardeningrevolution.com web site. I’ve seen it before but forgotten about it. Time to explore it again.
I have been using cattle panels a good bit, and have some new plans for this spring. I’ll see if I can find something like it that someone else has already done.
Hello, Stephen.
It’s getting around that time I start looking into my spring garden ideas. I grow mostly peppers which I’ve learned are about the most picky and even demanding of plants. The year before, I tried growing in garden boxes. And, they produced little to none. I’m thinking because of the heat, they were doing well enough to grow, but possibly too hot and unsuitable for producing fruit.
Last year, I tilled up a small plot and worked my red clay soil as fine as possible. I added some bags of garden soil and mixed the two together. My thoughts are that being connected to the earth, they get the nutrients and the roots can cool off suitable for both growing and producing. I learned that the hotter the pepper, the more water is needed seemingly. And with the water along with Miracle Grow (given a day every other week) I still couldn’t get the results I was looking for.
I’ve read often about raised gardens such as yours. I’m thinking a Pete moss mixture with garden soil and sitting on top of the earth would probably give every successful advantage to my garden. We’ll see how it goes!
John, this is a good example of things being very local. In our garden, the peppers grow and produce with almost no attention at all. It sounds like you like the hot ones, and we grow the sweet bell peppers, so that may be the difference.
I’m now focusing on regular in-the-ground gardening rather than my raised beds. This year, anyway. I’ve been grossly negligent in posting here – lots of changes in the garden over the past year or two that I need to write up. The raised bed garden is currently being used as a temporary holding area. I’ve got rose cuttings growing there, a couple of Rosemary plants that I wanted to save, and some sweet potato plants that will be transplanted into the main garden area in the Spring. My plan is for it to be mainly used as my cool weather garden, and the main garden will be the warm weather garden.