Cold Frame/Greenhouse/Potting Bench Post 4

The last post closed with the installation of the bench bottom.  I mentioned that gaps were left on the edges so water could drain off.  Here’s a photo showing the gaps, about 1/8 inch.  The 2 x 2 supports underneath have grooves on the side attached to the 1 x 8 bandboard.  Hopefully moisture can find its way out through these channels so it does not build up inside the greenhouse. 

With some more cedar 2 x 4’s on hand (boy that stuff is pricey) the project moved on.  The 2 x 4’s were ripped on the table saw into 2 x 2’s and used to make the bottom shelf frame.  Later I’ll put 1 x 2 crosspieces across the frame spaced about 2 inches apart to complete the shelf.  The temporary frame was removed.  I cut 1 inch off of each leg to lower the bench height a little.  Then a 2 x 2 ridge was attached between the top of the back legs. 

The little greenhouse at this point is a very rigid structure, a fact that pleases me greatly.    Rigidity translates to strength.  In fact I stepped up onto the bench and walked on it (that’s 180 lbs) – solid as a rock!  I’m confident that I can put bricks,  limestone pieces and large pots on the bench for thermal mass with no problems. 

Next the back wall went on.  First a piece of aluminum drip edge was installed over the back 1 x 8 to keep water from entering the unit.   

The top piece of siding was ripped at a 35 degree angle on the table saw to follow the angle of the 2 x 2 ridge.  The angles used are either 35 or 55 degrees.  For those of you who remember that class in plane geometry you took in high school, the two angles of a right triangle that are not the 90 degree angle always add up to 90 degrees.  The front of the greenhouse will face 35 degrees above the horizon – a good angle to catch the low winter sun. 

Here’s a view of the front of the greenhouse.  The aluminum drip edge stands out.  That’s OK because when the greenhouse is together I will staple Reflectix insulation onto the back wall.  That’s the stuff that looks like silvered bubble wrap.  It will not only bump up the R-value of the growing space but it has 97% reflectivity.  That should amplify the weak winter sun. 

The most challenging job is ahead – building the hinged lid that holds the twinwall polycarbonate panels .  I’m still trying to work out a design that will effectively keep weather out.  It looks like I’ll have to attach some hinges to some short wood blocks and try to model the real thing.  That means working in a cold pole barn as the winter storm is winding down.  Brrrrrr.   

(Apologies for the mixed fonts.  Blogger is being a pain today).      

Cold Frame/Mini Greenhouse/Potting Bench post 3

I added another descriptor to the name of this thing.  Now that the floor of the box is finished it looks like it will make a good outdoor potting bench. 

The stained pieces were dry on Monday and ready for assembly.  Just as in the trial assembly the front and back frames were built (or rebuilt) first, then the two frames fastened together by crosspieces.  The front 2 x 2 leg was replaced with a 2 x 4 leg.   Everything was squared and braced, and lastly a diagonal piece that makes the front roof was held in what looked like a good angle and marked.  Both diagonal pieces were cut identically, the back legs were cut to go underneath the diagonals, and the diagonals were fastened to the legs. 

At the end of the day the basic frame was together.   The bottom of the greenhouse is held by a temporary frame to hold the legs at the correct distance.  Later I will build a shelf unit near the bottom that will not only hold pots but provide the structural support that the temporary support frame does now .

I took my time putting the greenhouse back together.  I’d like to be able to make more of these units and sell them if they perform as I hope and if I can make them at reasonable cost.  That’s why I’m sweating the details on this prototype.  The lid and sides will be covered with the twinwall polycarbonate lites used in greenhouses.  This material is much lighter than glass, is very tough and has a higher R-value than a single sheet of acrylic or glass.  

This weekend I came up with the design for the sides.  It’s so simple that it took a week before the answer came to me.  Here’s the detail of how this works: 

The bottom of the side lite goes outside the 2 x 2 crosspiece, and inside the 2 x 2 diagonal (the crosspiece is flush with the inside of the legs, the diagonal is flush with the outside, leaving a small gap for the lites).  I meant to cut a groove in the back 2 x 4 leg that the lite would fit into but forgot, so I’ll have to tack a stop onto that leg to hold the lite in place.  Once the side lites are attached the side 1 x 8’s will be attached to the 2 x 4 legs.  (Yes there will be a gap between the 1 x 8 and the side lite).

2 x 2’s were fastened to the front and back 1 x 8's to support the floor of the greenhouse.  This floor will have to support a lot of weight - containers, seed flats, and maybe bricks for thermal mass - so I kept the 2 x 2’s high on the 1 x 8 to use it’s depth for load-bearing (think of the 1 x 8 as a sort of floor joist).   The 2 x 2 supports have grooves on the side that is attached to the 1 x 8 to allow water to drain out.  I installed the carsiding floor today and left a small gap at each end to let water drain.

 

I wanted to use red cedar for everything but after I recovered from sticker shock I realized that wasn’t going to happen.  Cedar carsiding is about 4 times the cost of pine, so I went with the pine and used cedar for the framing and the rough sawn pieces like the 1 x 8.  With several coats of stain and if there’s no standing water the pine carsiding should hold up for a while.  Cedar is not only durable but light as well as strong, but the expense is a deal breaker. 

Here’s the greenhouse with the floor installed.  I also installed some short diagonal braces at each corner to rigidify the structure. I’m really liking the look of the carsiding.  Tomorrow I’ll put on the back siding and maybe build the lid. 

 

Time to dig up the parsnips

I didn’t hold out a lot of hope for the parsnips.  I planted about 20 square feet of bed in them.  The moles were really bad last summer.  Either the moles or something else using their burrows  was eating the end of the roots and killing whole plants.  About half of the snips that I dug up were too damaged to use.  Most of them were a stunted globe with a number of taproots, or they had other damage.  These are the ones I kept, and some of these were later tossed.  I may not plant parsnips next year so the animals don’t come to expect a regular treat.  Total 3 lb 4 oz.

The two kohlrabi plants (9 oz) were pulled up.  They stopped growing some time ago and it looks like there will be real winter weather later in the week. 

I picked some more brussels sprouts (1 lb).  There's at least another picking on the two plants.

Cold Frame/Greenhouse - Protecting the Wood

It may not seem like progress, because the incipient mini-greenhouse (I still don’t have a good name for this thing) is now dis-assembled and the components are on sawhorses.  But it is.  The first post described the rudimentary assembly of the greenhouse frame.  The next day I saw that some changes were needed.   From the last post, this is the rough frame.

 

First the depth of the structure was reduced to 27 inches from 30 inches.  It was actually easy enough to do that.  First the diagonals were removed, then each end was reduced in turn, keeping the basic frame intact while I cut down the cedar 1 x 8 bandboard and the crosspieces of the bottom support frame.  Once that was changed  I held up the diagonals in their new position.  The smaller size looks and feels more “right”, whatever that is. 

Then I took apart the entire unit, leaving only the temporary bottom frame, which I will use again when it is put back together.  This is where using screws as fasteners really shines – all I had to do was back them out with a cordless drill.

I put all the wood on sawhorses for staining (why do they call it staining, it actually makes the wood look better?).  This included the carsiding for the back and bottom, so it was a lot of wood.  I set two 10 foot metal fence posts on sawhorses to hold all that lumber, and stained the wood on another set of sawhorses. 

Which brings me to the topic of protecting outdoor structures.  Most of my years working as a carpenter I put on the outside woodwork on high end homes – the siding, overhangs, dormer details, etc.  So I formulated a few simple rules for protecting wood exposed to the weather.   Here they are:

1.      Stain the wood BEFORE assembly.  That means putting it on sawhorses and staining the wood.  When the wood shrinks on exposure to weather it will not reveal an unstained area if all the wood has been stained.  If the pieces have already been cut to size then stain the end grains also. 

2.      Use a staining brush and roller pan, not a paint brush.  You won’t believe how much faster the job goes with this tool, and the stiff short bristles really work the stain into the wood fibers. 

 

3.      Stain both sides of any dimensional lumber.  That’s right, both sides.  A stained surface will absorb and release moisture at a different rate than an unstained surface.  Staining both sides makes the wood more stable and reduces the likelihood of cupping and splitting. 

4.      Once together the structure can get a second coat of stain.  This will go on much faster than the first coat. 

This is where the mini-greenhouse stands right now - on sawhorses.  I wanted to get some work done on it today but my lower back said no way.  Just as well, chair bound there was time to come up with a design solution for the sides.  Next post it gets put together and I’ll go into some detail on the design concept.  

Cold Frame/Mini-Greenhouse

I’ve been thinking about building an outdoor garden structure this winter, something for storing tools, growing seedlings and cold hardy greens.  I made a rough design of a shed, about 6 feet on a side, with a south facing window and a bench below the window opening.  From my years spent (or misspent) working as a carpenter and the books I've read on passive solar I had convinced myself that I could design something that would not only give plants good sun exposure but retain some of that solar heat gain on cold nights. 

I came up with some rough sketches but finally set the plans aside.  To build in the performance that I wanted the structure was going to cost more than I was willing to spend.  There was also no good level spot with full sun to place a shed of that size. 

I checked out some garden blogs for information on cold frames, but an in-ground cold frame wasn’t quite what I was after.  There was also a plan I found for salad tables.  Elevating the growing surface to countertop height definitely had an appeal.

Then I came across a plan for a cold frame/propagation bench from the Western Red Cedar Association:  http://www.wrcla.org/pdf/coldfr.pdf   This was more like it, a mini-greenhouse that you worked in from the outside, small enough to fit in the space available and with good looks.  The “glass” part is the hinged lid that the user lifts up to access the plants.  And best of all, the plants are elevated to a more comfortable working height, at least they are off the ground.  I set out to design a structure that was large enough to overwinter some greens and also harden off seedlings in the spring. 

This is the general idea of the thing on which my plans are based.  I drew up plans for a larger structure.  The depth of the box was increased from 2 to 2 ½ feet and the length from 4 to 5 feet. The planting box was raised - their plans had the box only 18 inches above ground.  As I looked at the drawings for ideas  I began to think that the designers never actually built this.  There were parts missing in the design that were structural essentials. 

I drew schematics of critical sections of the structure, but left many details to work out as it is built.  It’s really hard to get a sense of the “rightness” of the design until I can see it “in the flesh.”  Since all the components are screwed together, it’s easy enough to back the screws out with a cordless drill when I want to make changes.

The challenge in designing a small garden structure is to make it light enough to move but strong enough to last.  I’ve found that most garden structures use more wood than necessary, erring on the side of using more lumber than is needed so no high stress area has inadequate wood.   It's a challenge to find a design that works without weighing too much. 

The first day I set out to build the basic framework.

Here’s the front section, 2 x 2 cedar legs about 3 feet tall and a 1 x 8 cedar cross piece which will support the bench floor.  The 2 x 4 at the bottom of the photo is a temporary spacer to hold the legs at the proper distance.  Once assembled the section was squared and braced.  The back section was built the same way, but with 2 x 4 cedar legs 8 feet tall.  At this point I did not how tall the finished back frame would be so I used the full  8 foot 2 x 4, intending to cut it later once the dimensions are worked out. 

I attached the side 1 x 8’s to the front section.  

The front and back sections were supported upright on the floor and the unattached end of the side 1 x 8’s (top of previous photo) attached to the back section.  Additional braces were added to square and brace the structure.  The 8 foot long 2 x 4’s made the back section cumbersome to work with.  If I build this again, I’ll know the exact length to cut them, but the first attempt is a learning process.

A diagonal from the top of the front to the back legs was made 2 x 2’s.  When I’m satisfied with the geometry they’ll be marked, removed and cut to fit, but for now they are just screwed onto the outside of the legs to get a sense of the final dimensions of the structure.  I’ll see how it strikes me the next day and may move the connection on the back up or down a little, but this is the general sense of its form.  I’ll make another post in a few days on its progress. 

(Next day).  Well I had a look at it this morning and realized that some things should be changed.  First of all it seems too deep to reach the back easily.  I may reduce the sides from 30 inches to 27 inches.  Changing the depth will also reduce the height, which is a little high at about six feet.  I’m also thinking about replacing the front 2 x 2 legs with 2 x 4.  I may put wheels at one end and the 2 x 2’s aren’t large enough to attach wheels to.   Finally I plan to lower the box two inches.  All these changes should make the mini-shed more right-sized.  Now if I knew just what to call it.

Raised bed replacement

Last week I wrote a post - http://gardenvariety-hoosier.blogspot.com/2012/11/raised-bed-remodel.html - about removing the landscape timber frames on the two oldest raised beds.  The bottom rows of timbers were decomposing and I did not want to leave them break down in the soil as they are AC2 treated.   On Monday I put in a new frame made of yellow pine 2 x 8 anchored to stakes driven into the ground.

Building the beds was straightforward.  The lumber list consisted of six eight foot 2 x 8’s, a treated eight foot 2 x 4, and a pound of three inch anodized construction screws.   The two least straight 2 x 8’s were cut into four foot pieces for the ends.  The treated 2 x 4 was ripped into 2 x 2's and cut into stakes.  The box was screwed together over the bed.  I drilled 9/64" pilot holes with a power drill then drove each screw with a rechargable drill. 

 

Once the frame was built it was set in place and leveled by setting pieces of wood under the corners.  I wanted to keep the frames above the ground level but there’s a good bit of slope here so  I set the highest corner (on the right in the picture) into the soil about an inch.   Once the frame was in position I drove in stakes at each corner and attached the frame to the stakes with screws.  I had to accept some lean in the bed as the ground slopes too much to make the bed perfectly level. 

The new beds are a little wider than the old beds since the lumber is narrower.  I’ll probably just rake out the soil to fill the open space.  I guess I’ll get used to the look, but I like the old timber beds better.  There’s a lot of open space below the boards on the low side of the beds.  I’ll probably have to fill that in with a 2 x 2.

 

This is a good time to start making plans for next season.  The plans aren’t finalized but there will definitely be an expansion of the garden, mostly with self-watering containers and boxes.  The tree on the right is really too close to put more beds in, even though there is room.  There’s a chance it’s roots would find the nearest bed and start freeloading nutrients.  The stump in the foreground was a cherry tree.  Even though it was more dead than alive it still sent its roots to the nearest bed and nothing grew well in that bed until the tree was out.  That bed was thick with tree roots.

I plan to grow okra, pole beans, summer squash, and celery in containers.  I have one Earth Box and will have to build the rest from Rubbermaid containers.  I hope to build a Henley potato box as an experiment and am thinking about a way to plant sweet potatoes on the slope near the apple trees.  Last spring I trucked in a yard of dirt/compost to make the covered mound of dirt in the background.  It's held in place by a wood wall on the pond side.  I originally planned to put potatoes there but I'm now thinking about growing blackberries there.  Well I hope to get it all worked out by springtime, and it gives me something to think about as winter sets in.

 

Hiking at Brown County State Park

I usually hike at Morgan-Monroe State Forest.  It’s got some nice vistas, a few decent climbs, and it’s only 20 miles away.  Right now it’s gun season for deer and it doesn’t seem prudent to go hiking there, so I’ve been driving over to Brown County SP to get some hiking in.  This is a great time of year to hike when the weather is good – there’s no bugs, the leaves are down and the views are great. 

A number of counties in southern Indiana are hilly, but Brown County has the best hills.  At one time the county had a thriving artist community (TC Steele is probably the best known) who found something that spurred their creative impulses in the rolling hills.  The park is 16,000 acres but only the north half is developed with roads and hiking trails, and most of the hiking trails are in awful shape.  The southern half has only horse trails, and it’s about as remote a place as you can get in this state.

The one trail that I like is Trail 9, which goes into the undeveloped southern part of the park.  It consists of a 3 mile spur trail to a loop.  The entire hike out and back is 8 miles.  Most of the trail has been remade and is in good shape.  It’s also the most strenuous of the parks trails.  I used to go to the Smoky Mountains several times a year to get some hiking in (the hike up Mt. LeConte is my favorite) but that’s a 7 hour drive.  This hike would probably qualify as a moderate hike in the Smokies.  Most of the elevation changes from stream to ridge are 300 to 350 feet, but when you string them together it makes for a challenging hike.

The trail begins at Ogle Lake, actually a reservoir.  The trail angles up the hill on the right.

Once the first ridge is gained I can look out over the lake.  With the leaves down the views are very nice.

This is looking the opposite direction to the next ridge to the south.  The trees are not large here, I think it’s mostly because the topsoil is very thin and storms periodically knock trees down.  The trail doesn’t attack the ridge straight on because the slope is easily 45 degrees (down at the stream it looks more like a wall).  So the trail heads to the left and climbs the ridge then switches back to finish.

This is near the top of the ridge seen in the last picture as the trail is making the turn back to the west.  Out of breath here.  I’m really out of hiking shape and would probably have a hard time on a Smokies trail that gains several thousand feet.

Gained the ridge and looking back to the north where I came from.

Looking to the south at the next ridge to climb.  I was working at orienting myself to the landscape, making mental notes and trying to pick out things in the distance that I would find as I hiked there.  I spied a pine grove on the next ridge that I later walked through.

Continuing on the ridge, these chestnut oaks are the dominant tree on the hilltops.  I think they are the only tree that can thrive in the thin rocky soil  These are some larger than usual specimens.  In Jackson-Washington state forest, which is similar to this terrain, the state “conservation” department sold logging leases on the hilltops where they cut down the chestnut oaks.  They have little commercial value other than utility wood, as in pallets.  I can’t imagine how long it will take to bring back the trees there.

Down to the stream bed, now dry.

Then up the next ridge.  More huffing and puffing ensued.   

This ridge first ran east-west, then turned to the north.  This picture looked west.  I could see some farms and a red barn in the distance (in the center of the picture) so I must have been near the west side of the park. 

On the ridgetop the spur trail met up with the loop trail.  The trailmakers were kind enough to build a bench at this point which I was happy to use. Then it was onto the loop, which followed the ridgetop a ways, then dropped down to the stream, followed the stream, climbed back up the hill to the ridgetop again.   I hadn’t seen anyone so far.  It was very quiet except for the wind.  Nice to get away from everything for a while.

A large area of the hillside had only small trees and brush.  It looked like a storm had mowed down many of the trees here some years ago.

It’s interesting that there’s a lot of grass where the woods have been opened up.  I like this shot because of the way the shadow’s and branches all converge to the center. 

This stream has a little water in it. 

Back up the hill (more huffing and puffing) and full circle to the bench, where I stopped and had lunch.  Then it was a return on the spur trail.  Two more climbs and three descents and I was back at the car, total time 3 hours 15 minutes.  I’ll have to do this again before winter weather arrives.