During the first two summers we lived here, we planted over 150 trees and shrubs of various types, all supposed to do well in this hardiness zone (5A). (See https://eclecticmusings.blog/2020/06/18/usda-hardiness-zones/ for explanation).
Fourteen of them were eaten and killed by local antelope before we got our fence. Ouch! Several more were killed by the steers when they got out of their paddock and wandered around the property,
but most of the 75 or so that have died have not had such evident 4-legged “help” with their failure to thrive.
A lot of those failures perished as a result of early and very deep freezing – as in getting slammed with nighttime temperatures below zero (Fahrenheit) in early September when they still had leaves. Baby trees just don’t seem to appreciate those cold temperatures, especially not that early in the year.
Knowing that our soil is very sandy, and practically sterile (no worms or fungi, very few bugs…), I added a mix of peat moss, potting soil, and a small bit of rabbit manure to the holes of each of the trees before I planted them, assuming that the addition of organic matter would help hold moisture and provide some nutrients to the baby trees. I also added some mycorrhizal fungi to help the roots get established and mulched around them.
Watering was done every other day during warm weather, or whenever the soil test meter said it was starting to get a bit on the dry side.
In spite of all of this, last week I noticed that virtually none of the places I’ve planted baby trees has the tiniest hint of grass or weeds growing in or around those well prepared & well watered “holes” the trees were planted in!
Now add in the utter failure of most of my attempts at raising vegetables out here.
I was stunned!
Then it hit me that the ONLY gardening successes I’ve had have been in the raised bed I built right up against the south side of the house and inside the modified walipini (https://eclecticmusings.blog/2021/04/18/you-built-a-wala-what-i/) which also has raised beds and therefore controlled soil.
I mentioned my observations and frustrations to my husband (my PLAN had been to be growing nearly all of our veggies and grains and at least 10-15% of our fruit by this time). His astute reply was to look at the history of the pioneers in this valley who were on the verge of starvation for most of the first 20 or so years they lived here – which probably coincides pretty well with the length of time it took them to build up enough organic matter in the sand and gravel that constitutes this very alkaline (over 8.0 pH) “soil” to be able to sustain decent gardens. WHOA!!!! Now THAT was a revelation indeed!
Then it dawned on me that my only chance for growing the food we need is vastly more controlled conditions than what nature provides out here. Yes, I’m still working on building organic matter and soil fertility over the whole 10 acres, BUT, I’ve now realized that I need to focus my efforts on small areas, building them up quickly, and allowing time and animals to gradually help me with the rest of it.
After doing a lot of research, I’ve decided to try to build 12-13 sub-irrigated (watered from below the soil) raised beds this summer to provide good soil and steady deep water availability. These beds are reported to need about 30% less water than normal garden beds. I’ll use them for things like raspberries, blueberries, blackberries, asparagus, carrots, parsnips, and other cold tolerant root crops and veggies.
In addition, I’m adding hinged hoophouse covers to some of the boxes for growing more tender veggies. My hope is that the hoops providing 2 layers of plastic will provide not only frost/snow protection, but also further reduce water requirements by providing shelter from the vicious wind that blows almost constantly out here.
The first box is finished! Here’s what it looked like along the way. The pictures show the order we worked in while the text tells a better story of how we SHOULD have done it.
This one is built of 2×8’s with 2×2 corner braces. We built if fairly square, but it wasn’t quite all of the way square so needed a bit of truing.
Brace in place to hold it square (you can barely see it running on the diagonal, mostly covered with soil), it was time to flip it over and level it up, cover the brace with a thin layer of dirt, get all of the rocks out (HAHAHA! There’s a reason this is called the ROCKY Mountains!) and add a 2×4 frame around the top. This makes a place to sit while gardening as well as providing for the attachment of hinges for the cover.
The next step was to build a second 2×4 frame exactly the same size as the one on the box already and add a couple of good hinges to one long side.
Following this, we drilled holes in 1/2″ pvc pipe caps to hold the 1/2″ pipe that will form the frame for the plastic cover.
Next, the pipe caps were attached to the moveable hinged 2×4 frame, 3 on each long side, right up close to the inside edge of the long 2×4.
The pvc pipe frame consists of 3 pipes cut to appropriate length to make nearly a 1/2 circle. Figure the length by multiplying pi (3.14) times the diameter (that would be the width of your box – cap to cap) and then divide by 2 since we are only making a half circle. (for this box that would be 3.14*4=12.56, 12.56/2=6.28′ or 6′ 3.5″ If you are planning to add a second layer of plastic, subtract 1.5-2 inches from this for the first hoop, making it about 6’2″.
How much plastic protection do you need to add? Each layer will add about 1.5 hardiness zones to your area. For example, my area is zone 5A. Adding 1 layer of plastic will take me to about zone 6B, or about 10 degrees warmer than my normal coldest temperature. Adding a second layer of plastic will take me up about 3 hardiness zones, or to about 8A.
At least that’s the theory! The shortness of the non-existent frost-free growing season here is bound to also have an effect.
Next, we put a thin layer of hay over the dirt in the bottom of the box because it was just not possible to get all of the little rocks out of the dirt. I also used some expanding foam insulation to fill a couple of large knot holes in two of the 2×8’s so the rough edges wouldn’t cut holes in the plastic liner or allow a lot of cold air in to freeze that corner of the soil while the rest remained warm.
The hay was then covered with a layer of 6 mil black plastic that was stapled to the top of the frame, all around the inside, just below the 2×4 sit-on layer. In retrospect, I might have actually added the plastic before putting the 2×4 sit-on frame around the top, and I’ll probably try that on the next box just to see how it works out.
Once the plastic was secured in place, we cut a piece of 1″ pvc pipe about 2″ taller than the box and both 2×4 frames, drilled a bunch of small holes in one end to allow water to escape, then stood it in one corner of the box with the holes at the bottom.
Next came a 4″ layer of pea gravel for the water to diffuse through and to act as a reservoir for water for the plants above.
In the opposite corner, we drilled a hole through the 2×8 and plastic just above the 4 inches of gravel. We cut a 6″ piece of 1″ vinyl tubing and threaded it through the holes, then down into the very top of the gravel to act as a drain and let us know when the reservoir was full.
I got a bit ahead of myself here. Too excited I guess, and in too much of a hurry to get some transplants in that were getting just too big for my kitchen seed starting space. In getting ahead of myself, I put the pvc hoops on before getting the gravel in and level, and before getting the potting soil in and level. MISTAKE! I had to take them back out or make my sweetheart hold the lid open while I filled and leveled the “innards” of the box. In the picture above, you can also see that I’ve attached a length of chain to the corner of the box and a hook on the lid so I can brace the box open and hopefully have it not get blown away.
Once the gravel was in to about the right depth, I used the fill tube and added water until it began to form puddles in some areas of the gravel. This let me see precisely where the gravel was not level. Areas that were too high were dry while puddles were clearly visible in the low spots.
The next step, which I failed to take a picture of, was to fill the rest of box with a mix of raised bed potting soil and vermiculite to help hold water in the soil. If this bed was going to be exposed to rain or watering from above, I would have put a layer of landscape fabric over the gravel, but with the water all expected to wick up from below, I didn’t think it would be necessary for this box.
The frame for the plastic is made with 3 hoops of 1/2″ pvc pipe, 6 small screws, 6 pvc T joints that are 3/4″ to 1/2″, and some electrical tape. The T’s were used to hold the cross members of the frame and screws were put through them into the hoops.
Next, the screw heads were well wrapped with the electrical tape to keep them from cutting through the plastic and the middle joints were taped to hold the cross pieces up there.
Frame in place and secure it’s time to add some greenhouse plastic. Greenhouse plastic is vastly superior to the plastic you will find at your local home improvement center because it’s treated for UV resistance and therefore lasts quite a bit longer under constant sun exposure – a serious issue in this high desert. Standard 6 mil plastic will become brittle in the sun and fail, usually in 1-2 years, while greenhouse plastic is generally guaranteed for 5 years, and will often last longer than that.
The greenhouse plastic is held in place by screwing down a piece of 1×2 on each side.
Because it’s SO WINDY out here – all of the time, I then put down a layer of landscape fabric over the soil to keep the wind from blowing my good soil away while I was putting my transplants in and for those days when I will have the lid propped open to keep the box from getting too hot.
Since we’re still having near zero degree F. nights, I’ve also added a layer of AGRIBON agricultural fleece directly over my transplants.
We’ve had nighttime temps down to 6 degrees F since these were transplanted 8 days ago. The red cabbage was struggling even before transplant so I’ve started more in the house. Everything else seems to be very happy in spite of the cold nights. The wind, as usual, is doing it’s thing trying to blow everything away that isn’t nailed down, but, the kale, broccoli, spinach, Red Sails & Romaine lettuces are all happy and growing. One of the red cabbages looks like it might pull through, but I’m not holding my breath yet for it.
- Materials list for a 4’x8’x16″ self-watering (from below) raised bed garden (hinged hoophouse parts listed separately) This box, as of April 15, 2021, will cost just over $100 not including the gravel, landscape fabric, or plastic since I already had those on hand in large quantity. If you’re not planning to put in root veggies, you can save yourself a few dollars by using 2x6x8′ dimensional lumber and building a box that’s only about 12″ high instead of the 16″ high box I’ve built here.
- 5 – 2″x8″x8′ dimensional lumber (treated will last longer than plain and the plastic liner protects from possible toxic chemicals leaching into your garden and veggies BUT it will add significantly to the cost)
- 3 – 2″x4″x8′ dimensional lumber
- a box of 3″ deck screws
- 6 mil black plastic (or pool liner, but that’s more expensive)
- landscape fabric
- a scrap of 1″ or larger PVC pipe about 18″ long
- 6″ piece of 1″ diameter vinyl tubing
- gravel (if you prefer, you could substitute 96′ of 4″ perforated drain pipe with a poly-stocking wrap, but that will double your cost)
Materials list for hinged hoophouse cover for box above. As of April 15, 2021 a single layer cover will cost just under $60 and a second layer adds about $30.
- 3 – 2″x4″x8′ dimensional lumber
- 6 – 1/2″x10′ PVC pipe
- 6 – 1/2″ PVC caps
- 6 – 3/4″ to 1/2″ PVC T pieces
- 3 – 1″x2″x8′ dimensional lumber
- 1 – set of 2 hinges
- 1 – handle
- electrical tape
- 6 small flat-head screws
- 6 mil greenhouse plastic
- a handful of 3″ deck screws
- a handful of 2″ deck screws
- a length of chain and a hook if desired for wind protection
- a scrap of 2×4 to prop the lid open on warm/hot days