Category Archives: Soil

Building Raised Beds

This year, we added raised beds to our vegetable garden. This is not an activity that can be done in a day (particularly when you have kids), nor is it cheap. I’m sure some people find creative ways to make easy/cheap raised beds, but they would need to have a rare mix of resourcefulness and energy. However, despite the labor and costs required, we managed to put together some beds which will hopefully last a good number of years.

Why Raised Beds?

Last year, we had our vegetable garden right in the ground. It worked, but there were some frustrations which we thought raised beds could overcome.

The benefits of raised bed gardens are that:

Finished Raised Beds(1) The area is more set apart so people remember not to trample the garden and compact the soil. It can be difficult to remember where the edges of the garden beds were. I put some string between the garden beds and aisles, within the 14×16-feet fenced garden area, but the string didn’t last long. It was difficult to bring my kids over the rabbit fence because they didn’t remember where not to step. I don’t blame them, the weeds didn’t know where they belonged either.

(2) Good gardening soil can be added on top of existing poor soil providing a nice deep growing medium. I had been trying to improve the soil by working in manure and leaves, but since I didn’t know the history of our yard or what the soil composition was, adding good soil on top would make the garden deeper and more nutrient-rich.

(3) Square foot gardening can be implemented so that plants are grown close together and block out sun from weeds. Last year, I assigned plants homes in the garden almost randomly. It was hard to know how close together to plant them or to keep track of which locations seeds had been planted in. But when you look at a raised bed garden foot-by-foot, it makes it easier to plan ahead what to plant where, to maximize how many vegetables are grown in the space, and to fill in areas of soil where weeds would hope to grow.

Materials

The first thing we did for our raised bed project was to gather the materials we would need. We watched for a sale, and then went to buy the most expensive part: the cedar boards (cedar is a good wood as it is slow to rot). We wanted to enclose two garden beds, each 4×16-feet, with a brace in the center. Although I wanted the beds to be as deep as possible, we settled on 8-inches to keep the cost down. We decided that we needed to rent a truck to bring the wood home, since our car wasn’t long enough to transport 16-foot boards. We also needed deck screws to put the boards together and a new drill bit.

Cost of Raised Beds:
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Cedar Board 2x8x16′ (4 @ $38.87 each, less 11% rebate, with tax): $145.99
Cedar Board 2x8x8′ (2 @ $19.44 each, each cut in half, less 11% rebate, with tax, ): $36.51
Cedar Board 2x2x8′ (1 @ $4.44, cut in half, less 11% rebate, with tax): $5.21
Rental Pickup (to deliver the boards home): $23.68
Deck Screws (Triple Coated 3.5″ #9, 55-count): $7.08
Countersink Drill Bit (#10, 1/8″ pilot, less 11% rebate, with tax): $4.19
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Total: $222.66

The other component of the materials was to fill the beds. The Square Foot Gardening book by Mel Bartholomew recommends to fill a raised bed with 1/3 compost (5 different kinds), 1/3 agricultural-grade vermiculite, and 1/3 peat moss. We didn’t do that exactly, but we got it filled.

We had Terry Benjamin deliver Purple Cow Compost (3 yards) and Mulch. We used 1 yard of the compost for the raised beds and the rest was for another project.

Terry Benjamin delivered Purple Cow Compost. We used about 1 yard for the raised beds (remaining materials were for another project).

Cost of Growing Medium:
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Layer of Leaves: free
Layer of Homemade Compost: free
Purple Cow Classic Organic Compost (~1 cubic yard, with tax): $68.58
Compost Delivery Fee (with tax): $31.65
Vermiculite (1.5 cubic feet, 2 @ $13.99 at Menard’s, less 11% rebate, with tax): $26.27
Vermiculite (4 cubic feet from The Bruce Company, with tax): $34.80
Peat Moss (2.2 cubic feet compressed, 4 @ $7.49, less 11% rebate, with tax): $28.13
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Total: $189.43

Adding in the cost of the rabbit fence, it becomes clear that a garden is not cheap. However, if you consider that it costs about the same as 1-2 months of grocery shopping and will produce healthy food for years, it doesn’t sound unreasonable. When my kids ask for a snack and I’m able to pick fresh vegetables from our backyard to give them, you might even say that’s priceless.

Assembling the Beds

If you’ve done a lot of woodwork, you probably could figure out how to put the frame together. However, if you’re new to DIY wood work projects like we are, here’s an explanation of how we made it work for us.

The raised beds after being screwed together and placed within the rabbit fenced area.

The raised beds after being screwed together and placed within the rabbit fenced area.

To put the beds together, we made a template on a piece of paper with holes so that we could mark each piece of wood without a ruler (an 8-inch board is more like 7 3/8-inches wide, so measuring holes over and over isn’t fun). My husband inserted 3 screws at each corner, except for two corners where there were knots: there we skipped doing a hole in the middle. We put the 2×2 brace at the halfway point of the frame using one screw on each side. The countersink drill bit allowed us to insert the screws to be flush with the wood. Assembly was done in our garage on a tarp, so that we knew we had a clean level surface.

On March 30, we assembled the first raised bed. On April 5, we assembled the second raised bed. We then carried and placed the beds within the rabbit fence (it was a tight fit). We measured to make sure they were spaced evenly with the aisles.

Leveling the Beds

Just when you think that the raised beds are finished, you realize that your garden is by no means level. You never know that you have a hill in your backyard until you set the raised beds down and find that they look crooked. I wanted the beds to appear orderly and prevent water from running downhill, so the beds would need to be level.

There are two options I observed for leveling a raised bed. You can either lower one of the sides by removing soil, or raise the other side by adding some kind of support (soil, brick, rock, piece of wood). If you lower the frame, there will be less empty space inside (since the existing soil will rise). If you raise the frame, there will be more space inside to fill. We did a little of both, constantly pulling out a level to check our progress and standing back to see how it looked as a whole. We spent a couple weeks tweaking how level the beds were in relation to each other and the slope of the land.

Filling the Beds

Next, we needed to fill the garden beds. This was no small task either. After we purchased the materials, they had to be hauled to the garden beds. Our rabbit fence around the garden does not have a gate, since at 30-inches we can step over it easily enough. But when we need to add about 85 cubic feet (3.15 cubic yards) of materials, then you start to wish you could just push a wheelbarrow right up to the beds.

Spring planting is underway in our new raised beds.

Spring planting is underway in our new raised beds.

The bed had been a mix of top soil, manure, compost, and leaves from last year. Over the winter, many leaves were added on top for insulation. Some of these new leaves were moved to the aisles and some were mixed into the soil. We also mixed in some mostly finished compost from our compost bin. Next, we added the peat moss (16.4 cubic yards when uncompressed) and agricultural vermiculite (7 cubic yards). Finally, we filled the rest of the bed’s volume with Purple Cow Classic Organic Compost (about 1 cubic yard). We were pleased with the compost. Last year we had purchased some compost from the Bruce Company, and comparing the two, the Purple Cow compost has a finer consistency (no large chunks except wood chips). Both compost orders had some garbage in them (plastic bits, banana stickers). The finer consistency of Purple Cow would prove helpful for planting time.

Spring is Here!

And so, we managed to finish the garden beds in time to start early spring planting. Despite the costs and labor involved, I know it will all be worth it when we are picking fresh vegetables. Time will tell if we decide to add more raised beds in the future. We’ll see how the garden does this year.

Beginning Home Soil Testing

I had been wanting to test our garden soil for a while, so it caught my attention when I saw a soil testing kit at Blain’s Farm & Fleet. The Luster Leaf Rapitest Soil Test Kit said it contained 40 tests: 10 each for pH, nitrogen, phosphorus, and potash. With a $10 off coupon in hand, the $13.99 price tag went down to $3.99. This sounded like a great deal compared to a soil test from the University of Wisconsin’s Soil Testing Laboratories at $15 per sample (which includes the percent of organic matter instead of nitrogen). Let’s see… 10 professional soil tests: $150, or 10 do-it-yourself soil tests: $3.99. Why not?

Test kit and soil samples.

Test kit and soil samples.

What did I test?
I collected four soil samples:
* A – Vegetable Garden
* B – Nightshade Garden
* C – Patio Garden
* X – Purple Cow Organics Activated Compost

To collect the samples, I used a trowel to dig 4 inches down and then put some of the soil into a paper cup. I labeled the cups as I went and tried to avoid any cross contamination.

Was the testing easy?
Although it wasn’t exactly difficult, there were frustrations. I like to do things with precision, so I tried to follow the instructions exactly. But there were challenges with small and wobbly components, lack of detail in some instructions, steps requiring additional equipment, and waiting periods which made the process accident-prone and tedious.

First, manual dexterity was a challenge. I have small steady hands, but yikes! The tiny capsules were difficult to open and the powder had to be carefully inserted into a narrow test chamber. I found the only way to avoid powder poofing onto the table was to loosen the capsule slightly, hold it over the test chamber, steady my hands on the container, and then gently and slowly open the capsule within the narrow space so the powder would fall straight down. This worked ok, except that the color comparator containers are narrow and tipsy as well. There weren’t any major spills but I had to get powder off the table in a few instances and I held my breath whenever the containers wobbled.

The soil testing equipment took over our kitchen table. Here I was opening a capsule over the test chamber of the color comparator container.

The soil testing equipment took over our kitchen table. Here I was opening a capsule over the test chamber of the color comparator container.

Second, some of the instructions could have been written with more detail. For example, what is the best way to get a soil sample 4 inches deep? Is that the top or bottom of the soil collected? Do you measure including the layers of mulch/compost added on top? How much soil should be collected (later I realized it would have been nice to have more)? How should organic matter be sifted out? I read on Amazon reviews that the Luster Leaf company does not respond to inquiries, but perhaps consulting a soil expert at the University, their online instructions, or a Master Gardener could help answer some of my questions.

Third, it would have been nice to have a list of recommended equipment. I found myself contemplating how to do many of the steps because I don’t have lab equipment sitting around the house. I ended up using: a trowel, paper cups to hold the samples, a plastic fork to break up soil, kitchen measuring cups to measure soil, canning jars to mix soil and distilled water, and q-tips to clean the containers. Hopefully the equipment I chose was appropriate.

Fourth, the whole process took a long time. Although this was my first time doing these soil tests, four soil samples with four tests each took at least 5 hours over 4 days. This included collecting the soil samples, performing the tests, and washing out the equipment after tests. I combined steps and waiting periods whenever possible to save time and effort. The waiting periods included: waiting for the soil samples to dry out (about 24 hours), waiting for the soil to settle after mixed with water (30 minutes to 24 hours), and waiting for the tests to change colors (1 minute for pH, 10 minutes for nitrogen, phosphorus, and potash). I put all the equipment in a boxtop so that I could get it out and put it away as I found time to work on it.

What were the results?
The test results found mostly neutral pH and strong deficiencies and surpluses of nutrients. I wouldn’t be surprised to see low levels of nitrogen on a city lot, but I have a hard time believing that my garden soil (with many worms, nitrogen-fixing cover crops, and healthy-looking plants growing) doesn’t have any nitrogen. Or then again, perhaps the nitrogen is only in the top 3 inches of soil and the sample missed it. It would be interesting to send the same soil samples to the University for a comparison since I can’t say I completely trust these results.

Soil Sample pH Nitrogen Phosphorus Potash
A – Vegetable Garden 7.0 (neutral) Depleted* Depleted* Surplus
B – Nightshade Garden 7.0 (neutral) Depleted* Depleted* Surplus
C – Patio Garden 7.5 (alkaline) Depleted Surplus** Adequate
X – Purple Cow Organics Activated Compost 7.0 (neutral)*** Surplus Surplus** Surplus

* Result not confident. Solution may have needed further uninstructed shaking after color settled.
** Result not confident. Solution may have been shaken too much to dissolve settled colors.
*** Result not confident. Color of the solution not obvious when checked against comparator chart.

Nitrogen, phosphorus, and potash tests required mixing soil with water and then testing the water

Nitrogen, phosphorus, and potash tests required mixing soil with water and then testing the water

The pH testing required less soil and was quicker

The pH testing required less soil and was quicker


How confident are you in the accuracy of the results?
Overall based on color changes and results, my gut feel is that I was somewhat confident in the potash results, but not very confident in the pH, nitrogen, and or phosphorus results. Some of the solutions changed color immediately and very clearly, but some colors didn’t change at the noted 10 minute period of time or didn’t accurately match one of the colors on the comparator chart. For the nitrogen and phosphorus, I noticed that there was color settling at the bottom of these containers, so I shook them again and reviewed them after 20 and 30 minutes. In some cases, the color got darker as more of the settled color dissolved. As it was not in the instructions to do additional shaking or waiting, I’m not sure if the color at the 10 minute mark was accurate or whether the color failed to display correctly until the 30 minute mark. When testing the compost sample for pH, a blueish tint did not correspond to one of the shades on the comparator chart.

Conclusion
Even though I don’t find the results dependable, the soil testing was educational and fun. It helped me become more acquainted with the process and gave me the opportunity to think about and question factors influencing the results. If I go with professional soil testing, I will appreciate the service much more now, knowing all the steps involved.

The greatest value is in having accurate and helpful results. This makes professional soil testing for $15 per sample a better deal than the Rapitest do-it-yourself kit for $13.99. You don’t save much time per sample as you would still need to collect soil, fill out a form, and deliver the sample, but you wouldn’t need to fidget with small capsules, make a mess in your kitchen for days, and strain to interpret the results. Otherwise, if you want to try other do-it-yourself methods, there are a few articles online that suggest pH can be tested at home with vinegar, baking soda, or cabbage juice… But in the end, if you want certainty, go with a professional soil test.