Finishing the North Pit

With the trench behind the raised bed pretty well done, I need to extend the cement wall along the entire length of the fence. While the bulk of the digging in the pit is done, the edges need to be finished off. We have left about a foot of untouched dirt next to the fences, for stability while we were working.

For the cement wall, this means taking the edge of the excavated pit right up to the fence.



Continuing around the edges reveals more big rocks and also some irrigation pipes.



We need to decide if we take out the newly exposed rock, or just cement it in place and leave it there. Take it out. We took out all the rock along the edge of the pit next to the fence, and then, using our masonite pieces, made forms and poured a concrete wall down to bedrock.



It took 22 60 pound bags of Quikrete concrete mix for this wall (Home Depot, $51.92). Once the concrete was poured, we then mixed a bag of mortar mix and put the white limestone blocks on top.



We will wait a couple of days to let everything set, and then remove the bags of compost and forms, and then start shovelling dirt over into this corner. We will need to re-do the irrigation system where it comes under fence by the gate, and then back under the fence over in the corner.

Behind the Raised Bed

With the North Pit mostly done -- I'm still not sure how to finish it off -- we turn our attention to the strip next to the fence, behind the raised garden that would connect the North Pit and the South Pit. This strip is really weedy. It's only 4 to 5 feet wide and 16 feet long. It has no water supply (no irrigation), and is of variable sunny-ness, depending on what is in the raised bed. If I dig it up, I can continue the cement wall topped with a limestone brick on the top along the fence -- I'm inclined to do this treatment around the entire lot at the fence line.



But what to put back there? It's a pain to mow, and trim, this area. It's too small to really grow something; it mainly is used as a walk area to be able to get to the raised garden.

So, instead of putting in grass or a ground cover, the suggestion is to make it a walkway. In fact, to put a walkway all around the raised garden. If we put in a walkway that matches the sidewalk around the deck, it would match. That sidewalk was dug out, and then filled with stone and sand and decomposed granite, with flagstones put on top. That seems like a reasonable treatment for this area too.

The first step then is to dig it out. Starting on this, we find big rock from 2 to 8 inches under the soil. The soil is very dry, and easy to dig out.



At the moment, we will continue just taking the dirt off the top. But we need to decide whether we take the big rock out, or just cover it over, using the big rock as fill. If we take the big rock out, we will need to replace it with smaller rock to fill the space. The easiest answer is to leave the big rock there.

If we remove the big rock, however, we effectively trade the few big rock for lots of smaller rock. The big rock is easier to get rid of than the smaller rock. Plus there may be more dirt under the big rock, so removing it would give us a more stable finished product -- all inert rock and sand, without any shifting clay soil. On the fence side, we can do our cement wall with limestone block on top. I'm not sure what to do next to the raised bed.

A couple of days later ...

It was very easy to take out the big rocks.



The next step was to straighten up the fence side of the trench, to pour the concrete wall and put the limestone blocks on top. We needed to buy more limestone blocks (Whittlesey Landscape Sales, 640 pounds for $51.88). Plus I would need concrete (24 bags of 60 lb. Quik-crete, $56.64 at Home Depot).



As before, I draped some black plastic on the outside, to keep the concrete separate from the dirt on that side.


Then I used a set of 1x4 pieces of wood to keep the masonite form spaced from the black plastic, and poured the concrete in between. I used the bags of cow manure that I've been buying to mix in with the dirt (60 bags so far at 1.40 a bag, from Lowes and Home Depot). to keep the forms in place. I had to take special care around the fence posts.



And when the forms are removed, we have our wall.



Next, a little mortar and we put the stones on top.



And now we need to clean up the trench, getting it down to rock with both sides straight and clean, so that we can fill it up with rock.



The raised bed should be all pretty good dirt, so we want to partition it off from the trench and keep the dirt in/under the raised bed. We will use landscape cloth -- a weed barrier -- as a curtain to separate the dirt from the rock.

Once the weed barrier is in place, we can start filling the trench with the rock that we dug out of both the trench and the north pit. All that rock that we wheel-barrowed out to the driveway now is wheel-barrowed back. While it was on the driveway, we were posting it to Craig's List and so most of the larger pieces are gone; we have apple-size (and smaller) pieces left, which should be good fill.



This cleans off the driveway. We need a bit more rock for fill, and then to cover it with sand and decomposed granite as a base for flagstones.

Drip irrigation for the herb beds

One of our major expenses is for water. Specifically for watering the lawn and garden during the summer. We have a full automatic sprinkler system, but we would like to see about improving it -- being more efficient in how we water.

I went to a talk put on by the City of Austin which suggested drip irrigation. In particular, this was using a drip line, rather than the individual lines to each plant. I've been adverse to doing the individual plant lines since plants come and go and it seems like a lot of maintenance to keep up with it. A drip line, on the other hand, can be used to saturate an area, but from underground, rather than by sprinkling it thru the air. This should cut down on evaporation and misting and all that. We apply the water directly at the roots, in the ground.

At the talk, the speaker said I could find all the stuff at Lowe's or Home Depot, but I couldn't. I could find the area, and some of the micro-irrigation equipment, but not the drip line and all it's supporting units. But checking on the web, I found http://www.rainbird.com and it has provided what I need. It was not easy finding the information on drip irrigation, but there is more under "Professionals" instead of "Homeowners". In particular, if you ask for a Retail Store, you get the standard Home Depot and Lowe's, but if you go under "Professionals" and "Find a Distributor", you can get the name of places that sell actual drip irrigation equipment.

I went with the XFS Subsurface dripline. This allows me to put the irrigation line under the ground and saturate an area at the root line. Plus in this part of the country (Central Texas), it is not going to freeze below ground and it's out of sight. To start with, I simply want to do 3 beds -- the beds around the back porch with my Irises and Linda's herbs. When I put those in, I used Zone 5 just for them. So I have a complete zone dedicated to these beds and can switch the entire zone.

In the following photo, notice the 3 sprinkler heads -- one in the top bed and two in the bottom bed.



Similarly, in the Iris bed, there is one sprinkler head in the back corner.



(These pictures before the change are not current -- the irises are doing badly from the freezing weather, and, I believe, the lack of water, which is why I need to get this new drip irrigation in place.)

We started with the dripline (XFS0912250) and 3 1800 Retro units.



The 250 feet of dripline was $110.50, while the 1800 Retro units are $23.60 each. The idea is that the 1800 Retro units replace a pop-up sprinkler head. They thread onto a normal 1/2 threaded PVC pipe and contain both a filter and a pressure regulator to lower the water pressure to 30 psi. That means that we get out of the two outlets on the top (the "tee") clean water of the right pressure for the dripline.

I dug down in the bed to the bottom of the sprinkler risers that were there until I found the connection to the underground water supply. For the iris bed this was already a 1/2 PVC female connector, so just putting a 1/2 PVC nipple to connect the two female threaded pipes, I was able to thread the 1800 Retro unit right in.



Then I cut 8 feet of the XFS dripline and pushed it onto the tee. This was the hardest part. The designers at Rainbird made it easier, because the top of the 1800 Retro unit screws right off, revealing the filter.



With the tee separate from the filter and housing, I was able to shove both ends of the 8 feet of dripline onto the tee, creating a loop. I could then put the tee back on the top of the filter housing, and screw it on, and then bury the loop of dripline, up along one side of the iris bed and back on the other. Then a bag of mulch to cover everything up.




The same sort of thing for the other beds. First dig down and find the bottom of the sprinkler riser to get to the water supply. In this case, it turned out the connection was a 3/4 inch female threaded PVC, so I had to get two 3/4 inch male to 1/2 inch male adaptors. Using them it was simple to attach the 1/2 1800 Retro to the 3/4 inch water supply, about 12 to 14 inches down from ground level.



The upper bed needed about 12 feet of dripline, but I mis-measured (at the bed) and thought it was 13 feet. Once I had put the dripline on the tee, it became obvious that the dripline was too long, so I had to take it off one end of the tee and cut it a foot shorter. It was extremely difficult to get off the tee, so for the lower bed, I only put it on one end, then laid out the dripline to the right length, and put it on.



The bottom bed was much the same, but longer -- 24 feet of dripline. And it originally had two sprinkler heads, so I used one and capped the other off.



As with the iris beds, I buried the dripline a couple inches underground and then put a bag of mulch (4 bags altogether), over the top, to cover the dripline.

Everything went pretty smoothly. I started at 11:00 AM and was finished by 6:00 PM, and that included two trips to Home Depot for the 1/2 to 3/4 adaptors and for the mulch and lunch. There were two problems.

Just as I was screwing on the top of the last 1800 Retro, for the lower bed, I tightened it down and heard a "snap". Something had broken under ground. Luckily it was not the $24 1800 Retro, and it was not the water supply, it was the 1/2 to 3/4 inch adaptor. I was able to get it out of both the ground water supply end and the bottom of the 1800 Retro and had to go back to Home Depot to get another one (I got two to be sure I had an extra). So that was a delay, but worked out fine.

The other problem was that when I turned on the sprinkler zone, at the box in the garage, to test it out, it seemed to do nothing. Which is sort of what is expected. But walking over to the iris bed, I could hear a noise coming from the corner where the 1800 Retro and tee are. Digging it back up, I could see it was spraying water all over from the joint between the housing and the screw on top. I took it apart, cleaned it off and put it back together, tightening everything by hand. Same problem. I eventually used a pair of channel-locks (a very large pair of pliers) to tighten the head on as much as possible and that stopped the leakage. I dug up and checked the others; they were all right. I'm not sure why 2 of the 3 worked fine with hand tightening, but the third needed extra tightening.

Now the system is in place. You can't tell if it is on or not. After running it about an hour, most of the beds still seemed very dry, so maybe it needs to run longer or maybe this is not the best solution. The sprinkler system is set to run twice a week and zone 5 gets to run for an hour each time. We'll see if that is enough to keep the plants happy.

Measurements suggest that zone 5 uses 60 gallons an hour when it's running. I measured it twice. Once it used 57.6 gallons; the second time it took 66.8. With about 45 feet of dripline, this would be about 1.3 gallons per hour per foot.

Removing Rock from the North Pit

We dug all the dirt out of the pit north of the raised bed, resulting in a trapezoidal hole 12 feet wide and between 11 and 13 feet long.



Now we need to remove the rock, so that the pit is deeper. At the shallow end, it is only about 8 inches deep; we want it to be about a foot and a half. This requires removing a layer of rock from the pit. We are assuming that, as with the rest of the yard, the rock in our yard is layered, and we can remove just the top layer or so to get the depth that we want.

On Thursday, we used the jackhammer to start breaking the rock up, using what appears to be a natural fracture running diagonally across the pit. This works pretty well, and in the first day's work, we extract two large rocks, and a big pile of smaller ones in the corner of the pit.



We still have to lift one of the big rocks out of the pit, separate the smaller rocks from the dirt and move the rocks and dirt out of the pit.



We spent all day Friday lifting the rock out of the pit and cleaning up. Then on Monday, we went back to breaking up the rocks with the jackhammer. Tuesday was (a) moving the rock around to the driveway, and (b) moving the dirt over to the dirt pile.



On Wednesday, we were able to just use the pry bar and grubbing hoe to loose the rocks and take them around front. After moving the dirt to the dirt pile (and mixing it with leaves), we had a complete ditch from one corner of the pit to the opposite corner.



Thursday, we used the jackhammer to break up the smaller corner and start on the larger one.



And Friday was just hauling all the rock out of the pit and out to the front of the house.



This left just the one corner with rock. Using the jackhammer, we broke it all up.



And we then took it around to the drive way, leaving us with a level, empty pit.



This took another week, so the rock extraction from this pit took about a month. As long as it is empty, we need to think about how to finish it off, before filling it back up with dirt.

North of the Raised Bed

When I drove thru California, I stopped in Corning (Olive City!) and bought two new olive trees. I bought two olive trees over the internet back in February 2007, but one of those died. This seemed like an easy (and cheap) way to get back to having more than one. The suggestion is that you may need two to cross-pollinate in order to get fruit.

One of the new olive trees has been planted in the pit that I just excavated South of Linda's raised bed garden, which puts it near the just-moved Shin Oaks, and the first olive tree. It looked like the best place to put the second new olive tree would be North of Linda's raised bed garden. That way it would be close to the other two, but more or less out of the way. This area used to have an Asian Pear tree, but that didn't do well, and we took it out. So to start, this area is just grass.



First thing we do is remove the grass. It seems a shame to waste the grass, since it seems to be growing fairly well, so I'll try to take it up and transplant it to another part of the yard. In this case, I'll move it over the French drain, along the fence.

After the first day of digging, I have roughly half the grass removed.



To transplant the grass, I'm cutting down with the shovel, and then trying to take just the grass and maybe an inch or two of dirt for the roots, using the grubbing hoe, coming in horizontally just below the grass. Doing so allows me to peel off the grass and move it more or less intact.

Another day of work, and we have all the grass stripped off, and transplanted.



Now we can start digging the dirt out. As we do so, we encounter a fair amount of rock -- mostly loose rock of small to medium size -- no larger than a loaf of bread. The very top layer of dirt must have been put in with the grass; it's fairly good, clean dirt. But below that is a layer of construction debris and rocky, sandy from the house construction. We are finding pop-tops, some broken glass, wrappers, and even four foot sections of electrical wire.



Also chunks of asphalt. The asphalt is always the same thickness, about 2 inches thick, but is then broken up into random sized pieces.




Under this construction debris is the dark, heavy, native clay dirt. This can be harder to dig. When it is damp, it is heavy; as it dries, it becomes very hard. But we mix leaves in with it, and mix all the dirt -- the top layer, construction dirt, and the native clay -- mix all this up with the leaves and cart it off.

Because about 6 to 8 inches down, we hit rock -- the native limestone. It's fairly flat, but with some cracks and erosion. Once we get the the dirt removed, we will try to remove the rock.



The dirt that we remove, we are taking over to the area near the electrical box, where we were digging last. We'll pile it up there, and later, after the rock is removed, we'll bring it back.



Tuesday, more digging



And then Wednesday, more digging



And again Thursday, more digging.



Finally, on Monday and Tuesday, we finished with the digging.



The next step will be to start removing this bottom rock layer.

Summing up, it took 2 weeks to dig out all the dirt, separate the rocks and debris, for an area 12 feet wide and 11 to 13 feet long, from 8 inches to 24 inches deep. It's deep enough at the far end that I really don't need to remove any rock, but I do need to at the 8 inch deep end, and it's the ground that slopes, not the rock layer. The rock layer seems pretty level.

Moving the Shin Oaks

The purpose of digging up the pit was to provide a place to move the Shin Oaks. It has also been suggested that moving the trees should be done while they are relatively dormant.

The first step was to dig them out. I started on Monday. One day to dig the dirt out of the way -- remember that at least part of the dirt had been dug up before, and so it was fairly easy to dig it out again. By Tuesday, I could start with the jackhammer, trying to get the rock out. The objective was to dig down, more or less to bed rock, all the way around the trees. Wednesday and Thursday was more jackhammer work.

Once I was through the rock all around the trees, the trees themselves were sitting in a big ball of dirt on a layer of rock about a foot thick. Friday, I worked at breaking the rock up underneath the trees and their dirt. I managed to get the rock out of one side, and with effort to tip the trees over into the space where the rock on that side had been.



This exposed the rock on the other side, allowing it be broken into pieces and moved out of the way. With a lot of work, and two people, we were able to then roll the trees out of the hole, and drag them across the yard to their new home, leaving nothing but a big hole where they had been.



With the trees over in the new pit, I dug a new hole big enough for the root ball. Again, since this dirt had been recently (December) dug up and put back, it was fairly easy to dig a new hole for the trees. The new hole was roughly 70 inches by 40 inches and about a foot deep.



Pushing the tree into its new home, I then poured two trash cans of really nice composted dirt around the roots. Most of the dirt on the roots (but not all) had come loose in all the movement. I went back to the old home and got a wheelbarrow full of the old dirt and added it to the compost, then put back the dirt that had been dug out of the new hole, and shaped it into a berm around the trees, to allow water and mulch.



The main problem in the new location was that the trees wanted to fall over instead of standing up straight. They had tilted significantly in their old home -- I think to avoid the cedar tree that had been near them. I pulled them as close to upright as I could get them, poured the dirt around the roots to support this new upright posture, watering it and stomping it down.

But, to be sure, I got some straps and hooked them to the fence, pulling both trees to a nearly vertical trunk. The top of the trees still slides over, but it's a pleasant arch. I think if (a) the trees will live and grow in their new home, then (b) in some time -- probably months -- the new roots will hold them in place and I will be able to remove the straps. But I should probably wait until October or November. November sounds better; hurricane season would be over, and the trees should be going dormant again.

We'll need to see if the trees like their new home. These are hardy trees not used to water or good soil, so their is a possibility that the new location will be "too good" for them and they will not survive.


An update from March 31. The trees are alive. They are putting out new leaves. It's hard to see in the picture, and it's not a lot, but at least it's something!

Filling in the South Pit

December 2010

The pit is done (at least in the short term). Several days of shovelling dirt from the dirt piles in the back yard into the wheelbarrow and then dumping it into the pit has both eliminated the dirt piles, and filled in the pit.




The dirt in the dirt piles was what I saved from digging out the pit (and other parts of the yard). Mostly it would then be the heavy clay that is native to this area. But it also includes some amount of sandy loam that some contractor would have brought in, and some amount of better, composted soil that we brought in later. But still the bulk of the dirt is not very good. So to improve the soil quality, I mixed in 32 bags of leaves, and about 30 bags of "organic humus".

The "organic humus" is the least expensive soil additive from Lowe's. It's mostly semi-composted wood products. It looks like pine needles plus other stuff. The leaves were from the neighbors. It being Fall, lots of people rake up their leaves, put them in bags and leave them on the curb for the City to pick up. I picked up some of these bags and brought them home.

As I was breaking up the dirt piles and shovelling it into the wheelbarrow, I mixed both the leaves and the humus into the soil. The theory is that this will add organic compounds to the soil, and make it better soil. It certainly makes it lighter and airier. I expect it to settle quite a bit over time in the pit.

The two spots in the back yard where the dirt used to be piled are now just barren dirt spots.






I've tried to spread some grass seed and put down a layer of organic humus on the top of each area. If we were to get any rain, the grass might grow and help keep the dirt in place. If this doesn't work, I'll try something else next Spring.

I have receipts for 30 bags of the humus from Lowe's this month $46.76, plus there were probably a dozen from a previous purchase. In addition, it was taking days to move the dirt from the piles into the pit, so, since time was of the essence at this time of the year, I hired a day laborer to help with shovelling. $80 for a days work. This allowed me to finish up the digging in one day.