George’s Geodesic Greenhouse project – September and October

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September & October

Monday, September 3, 2012

Close-up of vent opener

I cut out some 1×2 oak strips for mounting. You can also see the strips of black weatherstripping that seal the window and the backing I installed. I may need to add some more foam strips, but I won’t know until the entire house is sealed up tight.

Some creative trim work on the vent

I had some extra gutter laying around, so I cut it apart and used it to weatherproof around the vent.

The curved part of the gutter forms a nice seal on the lower V sections. I squirted some gutter seal around the perimeter of the vent assembly and attached to aluminum with TEK screws. After using them a few times, I have to say that self tapping TEK screws are excellent for all your sheet metal needs!

Saturday, September 8, 2012

Rain Collection

This is another bit of engineering I am especially proud of. After building several rain barrels, the question isn’t how to divert water into the pond, but how to divert overflow back out once the pond is full. Also, I won’t want cold water entering the greenhose in winter when I am trying to conserve heat inside.

The gutter was a bit challenging as I tried to join 15 sections at a 12 degree angle.

The downspout directs water into the greenhouse. The horizontal part is leaning only slightly inward. This is the key to allowing overflow to escape.

Here is the other side of the wall where the rain water enters the pond:

Inside, I have a shutoff valve to keep water out when I don’t want it. The open T junction is part of my future sink system. It will allow sink runoff to exit and run out the back of my yard.

Filling the Pond

It’s amazing how much math I am using for this project. I take back all those times I said to my math teachers “when am I ever going to use this?” because now I am glad I can do it. My pond holds pretty close to 450 gallons. Because of the highly irregular shape of the pond, I was unable to use LWH measurements for volume. So I turned on my hose and timed while I filled a 5 gallon bucket. Then I kept track of time while I filled the pond and there you have it: Tp/Tb*5.

You may be thinking “duh, of course that’s how you do it,” but I’m pretty proud that I figured that out on my own…

Saturday, September 15, 2012

Added some stone around the perimeter

This should seal out air for now and provide drainage, but I’m still working on insulation at the base.

Some more pond work

I added a 325 GPH pump for some circulation, put in 6 goldfish for insect control, and added another course of stones over the liner. I’m not sure how I am going to finish the top.

The planks helped to work in the back without having to jump in the water. We had some cold nights this week so I moved my tropical plants inside.

Pond Pump

I set up a pump temporarily to keep the water moving and aerated for the fish. I thought it would be a good idea to put the pump inside this bait bucket. It will keep it off the floor and the away from the muck (that will inevitably develop) and the perforated bucket lid makes a great pre-filter.

I have plans to make a waterfall, but for the time being I just tied the outlet tube to my PVC rain drain. I really want to get a rainy day so I can see how it fills!

Some work on the subterranean heat system

I bought another 30′ of drainage tube. It comes up out of the ground on the north side and will run along the perimeter behind the pond. Still looking for a fan to push the air through. I though of stopping by the RV store. I think they might have some DC fans for refrigerators. We’ll see.

Here we have it coming out of the ground:

Then behind the pond

And here it exits:

I will bury all of it but the outlet by the door.

Trying to find (found) a 4″ inline fan (DC 10 watt or less!)

I have added a 3′ length of PVC to my subterranean pipe. They make inline fans for boats that fit right over the pipe, but they draw a lot of amperage and move a lot of air. I don’t need much, but I am only finding cooling fans for computers that will require adaptation. What can I use that is somewhere in the middle?

Update 11/12/12: I meant to return to this post and let everyone know that I ended up getting a 4.75W fan at Radio Shack. I wired it directly to a 5W solar panel and it is working beautifully. Look at later posts for more details.

Sunday, September 16, 2012

Starting to look a bit like a greenhouse!

I looked in the door today and said Wow! I finally feel like I’m getting somewhere.

Sunday, September 23, 2012

My first crop

I couldn’t wait to get the flower beds in, so I put some lettuce and spinach in pots. I started them in my basement under lights, and since it was time to transplant anyway, I thought I would try out the greenhouse.

So the race is on. We’ll see how the indoor plants do through the fall compared to the same seedlings in the raised garden bed. The soil composition is essentially the same (compost and topsoil from my yard) so the major variables will be temp and moisture.

Monday, September 24, 2012

Painting the door

Last night it got pretty cold. I need to seal this thing up! If you remember, I picked this old door out of the trash and replaced a window pane. Yesterday I sanded it down a bit, cut it to size and now I am applying a new paint. Ace brand porch and steps paint. I think it will hold up nicely.

Went to the quarry today

If you have a truck and a quarry nearby, it is definitely worth it to buy from them! I paid $10 a ton for 2A modified stone compared to $25 at the garden center. Plus it was a cool experience watching a working quarry do its thing. If you want a prettier decorative stone, then the quarry might not be the place to go. I am lucky enough to have a place about a mile from my house that sells gray: small, medium, large and some mixtures.

Give them a call before you go to see what the rules are and if they sell small amounts to homeowners. In my state (PA) they ask for your vehicle/trailer registration and see what your GVWR is, then they will only load you according to what the tare weight comes out to. Rules are probably similar in most states.

I can’t wait to take my son here! With all the books he has with giant loaders and dump trucks, plus his fascination with any toy tractor or Tonka truck, he would love to see the real things. Maybe in a few years when he can ride in my front seat…

Wednesday, September 26, 2012

Filled in the floor with stone

I got a large roll of medium-grade weed fabric a few years ago and I have slowly been eating away at it. Well today I finally finished it. That and a couple of tons of 2a stone and I have a new floor in my greenhouse. I thought about buying some good ground fabric (it’s not expensive) but decided to make do with what I had. I wasn’t going to do anything else with it anyway.

Next step: solar pump and fan

I am waiting to get paid next week, then I plan to buy a 15W solar panel and a 15 watt dc pump. The pump I have chosen is the Sun-15 from Sun-Pump. The few reviews I have found have been positive, and the pump has a maximum head height of 9’11″, which will work perfectly with my idea for a solar collector.

So far the search for a 4″ fan has been tough. I want a fan that draws between 5 and 10 watts, which is proving to be difficult. The search continues.

Friday, September 28, 2012

Wondering about using tires for raised beds?

Does anyone out there have feelings about the use of old tires to contain the soil in my greenhouse garden beds? I haven’t done much research on the pros and cons of old tires. I like the idea of driving around and picking up the trash from the side of the road. Free supplies and helping clean the neighborhood feels doubly good. I like the ease of construction–just lay a few courses of tires and fill with dirt. I like the idea of circular flower beds in my circular greenhouse.

I guess my concerns are poisoning my plants or poisoning myself. Is there any danger to recycling old tires to grow vegetables in?

Learned a little about mushroom compost today

Mushroom soil is the most wonderfully rich additive to any garden for moisture retention, softening of hard clay, improving drainage, and just plain addition of beneficial nutrients. I use it all over in all my flower and garden beds, and I even spread it around my yard to feed my grass. It is soft, spongy, lightweight, easy to shovel and work with, and a deep black color that screams richness, and the best part: it’s cheap.

In my town, mushroom soil is sold everywhere for $10 a yard. I knew it was the spent growing medium from the mushroom industry, and I suspected from the smell that it was made from manure. I didn’t know if it was treated with any kind of chemicals or if it was safe for organic gardening, so I did a little research.

Yesterday I came across an article about mushroom compost and I decided to email the author, a Penn State professor. Very graciously, he responded quickly with an answer. No, he said, mushroom soil is not treated with chemical fertilizers or pesticides, and it is commonly used in organic gardening. This was excellent news. Here is a link to the article if you would like to read more: http://www.mushroomcompost.org/faqs.htm

For anyone who is looking to enrich their soil, this is a must-try.

The lettuce race is over!

I forgot about another variable. Rabbits! In less than a week they devoured every one of the outdoor romaine plants. Yeah I could have put up a fence or planted them in one of my raised beds, but the greenhouse plants are clearly the winners of this contest.

Can’t see the lettuce? That’s because it’s gone!

The indoor plants, on the other hand, have nearly doubled in size this week, and have required very little watering. Humidity levels inside the greenhouse allow me to skip days of watering.

Saturday, September 29, 2012

Turning my chile peppers into perrenials

or at least I am going to try. I was listening to Mike McGrath this morning on NPR and he taught me something very interesting. It seems that pepper plants are not annuals and can live for years under the right conditions. This is amazing! To think of all the work I have invested for the past decade of propogation, care and waiting all summer for peppers to ripen. He said to dig them up, pot them, bring them inside before frost and keep them under fluorescent lights for the winter.

Here I have potted a few of my fire-hot aji omni-color chiles. I gave them a pretty heavy trimming and will keep them in the greenhouse until temps drop below 50.

The door is on

I fitted the door and started some of the stops and trim work. Now that all large hole are sealed there is a noticeable rise in temperature inside, even when the clouds are out and at night. This makes me very happy!

Outside temp was around 71 today. 84 inside at knee level when the sun was shining. Not bad!

Temporary filter for pond

The pond water is getting very cloudy from algae. I set up this bucket with large stones at the bottom, gravel in the center and Hydroton rocks at the top. I also saved some of the rabbit-chewed romaine plants from the garden and set them in the hydroton. We’ll see how the pond water works for aquaponics as it stands right now and whether the plants and filter can help clear the water until I get a proper system set up.

Sunday, October 7, 2012

10 degree differential

is the average between outside and inside. Today the high was 52 and the greenhouse stayed a steady 63. It felt great inside. Granted, a front blew through yesterday and brought Fridays 80 degree weather way down. But still very encouraging to know that it can handle a 24 hour dip in the weather. Very high humidity, but the tropical plants seem to be loving it. We still have yet to get our first frost, and that will be the real test.

Monday, October 8, 2012

I found this cheap vent today

It’s amazing how I have walked down this aisle and never noticed this excellent auto open/close vent. It’s made for a foundation, but could be adapted for any number of uses. I just might have to cut a hole in my wall and put this in, just because it’s under $17.00! Anyway, I hope this helps.

It has a screen, screws for mounting in a rough-cut hole, and a nice plastic face cap for a clean look and easy insulation. It opens at 70 and closes at 40, which I don’t love, but it might be perfect for someone else looking to just keep from overheating.

Tuesday, October 9, 2012

I got my 5w solar panel in the mail today!

This is the exciting stuff. I picked up a 4″ fan that can push 72 cfm for $14.00 at Radio Shack. The solar panel cost 19.99 on Amazon with free shipping. Can I heat my greenhouse indefinitely for $35.00 using the power of the sun and the earth? We’re going to find out very soon. I have quite a few steps before I can get these installed. I need to test the fan and panel and build a housing to fit to the duct work.

Wednesday, October 10, 2012

Building the housing for the fan

I figured the easiest way to fit the square fan to the round tube would be with plywood. I am sandwiching the fan in between several layers, with caulk in between each layer to seal out air.

Here are the four sections I plan to use. I first cut out the holes with a saber saw, then I cut the four pieces apart. It’s easier to saw the holes out when you can clamp them to something.

And here it is nearly assembled.

Lettuce and spinach doing great

The spinach outside hasn’t done much at all, but the plants in the greenhouse will soon be ready for harvest. Not bad for a few weeks!

The subterranean system is running!

First I started hanging the Reflectix (semi-rigid bubble wrap insulation) above the pond:

Then I hung the 5w panel:

Finally I ran the wiring and connected:

Air is slowly moving out the end of the longest tube, so I would consider it a success for now.

I really have no way of testing the effectiveness of this system. I is pretty much just a good theory that pumping heated air underground during the day will radiate up at night. I guess I could disconnect and test the nighttime temps with and without the fan running, and maybe I will do that when it gets really cold…

Monday, October 15, 2012

Some finishing touches on the fan intake

I found this square drain that can hold a 4″ tube pretty snug:

Then I cut out the grate and the inner ring to maximize air flow:

Then I caulked the edge and screwed to my fan housing, then attached the intake tube and ran the tube up to the ceiling where the hottest air is.

I am being careful to block off the ends of the tube so no critters get in there and make nests! I wouldn’t want to have to get a snake to clean them out, so here is my 1/2″ mesh end cap.

Monday, October 15, 2012

I am thinking about an experimental green roof.

I am trying to do something useful over the doorway. So far I have put down plywood and laid some rubber roofing (pond liner) on top. I would love to build some walls around it and throw some compost up there. Any thoughts out there?

Air is moving nicely through the sub system

When the sun came out I stuck my face to the end of one tube and found that air is moving quite fast through the system. Now I just need a thermometer with some temp sensors to stick down there and test.

Built a better pond filter yesterday

My bato bucket didn’t work very well for filtering or for lettuce production. So yesterday I set out to build a proper filter with materials I had laying around. Note that I am experimenting with items I don’t have to buy or replace, so we will see how this one works.

First I took a 5 gallon bucket, some 1/2 inch PVC and fittings and some screen:

The idea to make the water cyclone wasn’t my idea but the idea of the brilliant people at SkippysStuff.com. Visit their site for all kinds of great pond-building advice.

Then I added a few bio bags from the fish store. One of them I pulled directly out of my fish tank in my house. The thought is that some of the beneficial bacteria that keeps the tank clean will help the pond.

Then another layer of screen and some sand, stone and Hydroton. I figured it can’t hurt

Now we will wait and see what happens! It’s an eyesore right now, but I have other things to worry about as freezing weather approaches!

Monday, October 15, 2012

I am thinking about an experimental green roof.

Sunday, October 28, 2012

Adding to the inner film layer

Not much going on. I have been working on other projects. Slowly (when the sun isn’t out and it’s cool enough to work inside) I have been stapling up more anti-condensate thermal reflective film on the inside. Sorry no pictures, they don’t show much.

I have also planted some fall crops. Beets, lettuce, parsnips, carrots, radish from seed. I’m not expecting much. Light levels are getting low. We’ll see what happens.

Wednesday, October 31, 2012

Still warm inside

After 6 straight days without sun and the window open during a hurricane, the inside temperature is still 10 degrees higher than outside. I am pretty pleased with the performance so far. The real test will come when it freezes outside.

The outer shell does leak in several places, but I am hoping that I can get the inner film layer to divert the water down where I will collect it.

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