A Tale of Two Raised Beds

Some of you followed along as Dianne built and planted her raised beds.  I used her method when I built some raised beds last fall.  Unfortunately, the place where we "planted" those beds was deemed unacceptable by the contractor who is renovating our house.  So early this spring, we moved them to our next door neighbor's yard.

When we transported all of the fill, we were able to put all of it into one of the frames, due to the natural decomposition that took place over the winter.  That meant that one frame was empty, of course.  I didn't have time to go through the method that I used in the fall - layering shredded newspaper, shredded leaves, topsoil, and manure - because I wanted to be able to plant for this summer.  I remembered a mix from Square Foot Gardening, looked it up, and filled the second bed with it.  The formula is 1/3 peat moss, 1/3 vermiculite, and 1/3 compost mixture.  For the compost mixture I used cow manure, composted chicken pellets, some fish emulsion - basically all the different kinds of compost I could get my hands on one Saturday morning!

In mid-April, I planted tomatoes and herbs in Bed One (with the original fill) and yellow squash, zucchini, zinnias, and cucumbers in Bed Two (with Mel's Mix.)  The difference is astounding.

Can you believe it?

As it happens, I got a soil test on Bed One that showed a pH of about 7.4.  That's on the high end of what is recommended for vegetables.  One of the symptoms of a higher than desirable pH is chlorosis, where leaves turn light green or yellow, but veins remain green.  This is what is going on in the tomato bed.  The soil test also recommended that I add nitrogen as the plants became established.  What with trying to finish up the renovation, I haven't been paying too good attention to these beds.  So last weekend I added aluminum sulfate (to lower the pH) and nitrogen to the bed.  I also sprinkled some Epson salts around the tomatoes, per Dianne's advice.

I'll take another photo in a few weeks so that we can see if there's any improvement.

P. S. - Dianne is amazed as well and plans on changing her recommendation re the fill for raised beds!

Raised Beds Revisited

You may remember that last year Dianne had a workshop at her home to demonstrate how to build a raised bed.  (See Part I, Part II, Part III.)  This last weekend my wonderful husband, Walter, (and our wonderful neighbor, Raymond) built two new 4x8 beds plus a 2x2 bed for Raymond's little girl, Alice.  Alice was a big helper!  This morning I helped out at PAR Collierville as third-graders from Collierville Elementary School toured the garden.  We explained the benefits of raised bed gardening to them and some of the parents had questions.  So I promised to post details about what I'd done this weekend.  I'm going to break this down into what it takes for one bed.

Per Dianne's advice, we went out to Germantown Lumber to get cedar to construct the beds.  Remember, you shouldn't use treated lumber because of chemicals that can leach into your soil.  Charles Speed, the owner, listened to our plans, then advised us to use cypress instead of cedar.  He said it would last just as long and cost about half.  Well.  We bought 2x12 boards.  He cut them into the correct lengths for us: two 8' lengths and two 4' lengths.  We also bought a 1x8 board and cut it ourselves (don't you like that "ourselves" part??) into eight 4" pieces for the corners.

from the Yellawood Raised Bed Project

Since we bought 12" boards for the frame and 8" boards for the corner pieces, we centered the corner pieces on the frame.  In the above picture, the corner pieces and the frame are the same size.  Centering the pieces gave us the advantage of being able to pick the whole thing up more easily.

The guys put some weatherproof glue on the ends where they joined together, then used 3" deck screws to screw the pieces together. They put the same glue on the corner pieces, then attached them with 2.5" galvanized exterior common nails.  Voila, the frame was built!  We let it sit inside the garage overnight so that the glue would set.

They put the frame where I wanted it, which was in a area previously used for a holly hedge that was removed a few weeks ago, included the stumps.  So it was bare ground.  If you're going to place it on a grassy area, lay down some corrugated cardboard and put the frame on top of it.  That will kill the grass.

Next we used the lasagna method to fill the bed.  We put down four cubic feet of topsoil (four 1 cf bags), then a layer of shredded leaves, then a layer of shredded newspaper, then half of a 50 lb bag of composted cow manure.  We repeated these layers, then topped the bed with another four bags of topsoil.  I soaked each bed and now the layers will start "working."  I'll probably have to add some leaves and topsoil during the winter because the level will drop as everything starts decomposing.  I'll be judicious about the leaves, 'cause I want everything to be composted by early next spring so I can start planting.

You may be wondering about the shredded newspaper.  I did a raised bed last year and tried to shred newspapers with my little home office shredder.  It worked ok, but it was S-L-O-W!  So I've saved my papers for a while instead of putting them out for the recycling truck.  I took them over to Shred Shop of Memphis at 318 Collins Street.  They'll shred your newspapers for you at a cost of $10 for the first 25 pounds and $.25 a pound after that.  It's a deal.  Turns out I had 32 lbs of newspaper.  I was so happy.

So, total cost for one bed:

          Lumber                             $80
          Screws & nails            10 (but we had lots left)
          Topsoil                                21 (16 bags @ $1.30)
          Cow manure                         5  (one 50 lb bag)
          Newspaper                           6 (about 15 lbs)
          Leaves                                  0 (plenty of leaves around!)

                      Total                   $122

A good time was had by all!

Dianne's plantings

Master Gardener Dianne Parks is sharing her raised bed gardening journey with us.  She installed two 4x8 beds last year.  Planting for this year has already begun!

The garden on March 1

The whole garden is now planted. I started planting Feb. 5, and finished on Feb. 25. I was worried because the radishes weren't emerging as fast as everyone says. I see that a few more are coming up now, but I planted more in the bare spots, which will help stagger the harvest anyway. I also read that radishes need fine soil contact and my garden is still pretty lumpy!! I will be glad when it gets more crumbly. Seems like everything is taking sooo long to emerge, and I start getting concerned it's not working. But today I am finally seeing the snow peas that I planted on Feb. 14 emerge. The original leaves of the romaine have wilted and melted into the ground, but new strong green shoots are taking their place. This is definitely a lesson in patience. Spinach, swiss chard, beets, kale and collards are yet to emerge….more patience needed. I have netting over the entire garden to keep critters from digging up seeds. Once vegetation starts filling in I will remove it.

Raised Bed Gardening - The Soil

This is the second in a series of posts about Raised Bed Gardening.

Now for filling the beds.  We learned at the Plant-A-Row garden at Davies Plantation that the fill is critical.  We first filled those beds with a mixture that was advertised as being "the best" for gardening, only to discover that it was completely sterile.  Nothing, and I mean nothing, grew in it.  We amended it, we turned it, we cried into it.  Finally we shoveled it all out and started over with our own mixture.  Backbreaking work. 

There are several methods, but here we'll discuss two of them, one slow and one quick (for us folks who need immediate satisfaction!)

Our friend Dianne used the lasagna method, which takes about six months to produce good soil.  Start with a couple of inches of top soil.  Add a thick layer of shredded leaves (the shredded part is important!)  Keep alternating top soil and shredded leaves.  The leaves will break down (the finer they're shredded, the faster this process), so just keep adding more layers.  Additionally, you may add items like coffee grounds, untreated grass clippings, finely chopped kitchen scraps (not meat), shredded newspaper, etc.  Get the picture?  You're producing a compost mixture!  Keep it damp to encourage decomposition. 

Now the fast way:  You'll fill the beds with a mixture of 1/3 each of vermiculite, peat, and a compost blend.  You need equal parts of each, measured by volume, not weight.  The vermiculite should be asbestos free - coarse vermiculate, medium grade is best.  It's most cost effective to buy the peat moss and the vermiculite in 4.0 cubic foot size bags.  The fill is where you'll spend the most money, but it's the most cost effective part of the project.  Fill once, harvest often!

A word about the compost.  Notice that we said "blended compost."  This means you need to mix together at least 5 different types of bagged compost.  That's because most commercial composts have only one or two ingredients.  If you mix together several of them, you'll get a good mix.  So look for worm castings, composted cow manure, organic humus, etc.  Mix them together by volume, not weight.

How do you calculate how much of each component you'll need?  Multiply the width and the length of your box, then divide a factor which is the depth of your box divided by 12.  For example:

Your box is 4x4x6-inches.  4 times 4 is 16.  If your box were 12 inches deep (one foot), you'd have 16 cubic feet.  But since it's only 6 inches, you need to divide by 6/12, or 1/2.  So the cubic feet in your 4x4x6in box is 8 cubic feet. 

In this example you'd need 8 cubic feet total, which would be 2 2/3 cubic feet each of vermiculite, peat moss, and blended compost.

Too complicated?  Do you now regret dozing in math class?  Do this:  make sure one of your compost bags is 2 cubic feet.  Carefully open it by cutting off the top.  Empty this compost into a container.  Then use this bag to measure your other ingredients.  You can eyeball the 2/3 part - it will be a little less than half of this bag.

Remember that you need to blend your composts first.  So take your bags and put equal parts from each into a separate container or pile or however you want to mix it into a blend.  Then you're ready to start mixing the 1/3 mix.

Lay a tarp on the ground.  Place the compost blend on it first, then add the vermiculate, then the peat moss.  Mix as best as you can as you go along, lightly misting to control the dust.  A dust mask is a good idea here, too.  After everything is on the tarp, pick up the tarp corners and roll the mixture around to mix it better.  This is a good two-person job.  Then drag the tarp over to your beds and start filling.  Water the beds well as you go along.  Don't worry about tamping down; everything will settle on its own.

Continue blending, mixing and filling until your beds are full.  Now you're ready to plant!

Next:  Dianne shares her planting experience.

Raised Bed Gardening - How to Build a Bed

Dianne's raised bed - just planted

This is the first in a series about Raised Bed Gardening.

At Winter School this year we were treated to a demonstration of how to start a raised bed garden. 

(Have you noticed the Winter School theme in recent posts?  If you're a Tennessee Master Gardener and you've never been to Winter School, please think about attending next year!  If you're not a Tennessee Master Gardener, find out how to become one here.) 

Our fellow Master Gardener, Dianne Parks, started a raised bed garden last year and has graciously offered to let us follow her progress.  We're going to blend her experience with what we learned at Winter School.

Dianne followed the instuctions on the Yellawood site to construct her raised bed.  Note, however, that Yellawood itself is treated and is not suitable to use for the actual bed.  Dianne chose cedar because it is long-lasting and won't warp.  To extend the life even further, she gave the wood two coats of linseed oil.  (Use pure raw linseed oil, not the boiled, which has petroleum additives.)  Other suitable materials include cypress, larch, and even some of the new non-wood building materials.  Just be aware of the toxicity of any materials used.  Dianne found that she was not able to get cedar at the big box stores, but had to go to a lumber yard.  The good news is that they cut the boards to size for her!

Speaking of size:  you don't want to go any wider than four feet.  The key to raised bed gardening is NEVER step into the bed.  Four feet is a width that allows almost everyone to reach into the the center of the bed from the side.  I put in a raised bed garden several years ago and established six beds that are 6x6 feet square, strictly for aesthetics.  I so regret that now, but not enough to redo the beds!  A depth of at least 8" is recommended, with a minimum of 6".  Note that some plants will like it deeper.

Use screws instead of nails to connect the boards, to further minimize warping and nail popping, then use "L" clamps to connect sections, if desired.  Dianne's final bed was two 4x8 foot sections.

You can lay hardware cloth or weed block cloth on the ground, then place your frame on top of that.  This will help control those pesky critters and weeds.  Do not line with plastic, as this will prevent earthworms from getting into the soil in your beds.

Next:  Filling the beds.