Thursday, October 29, 2015

Building Mini Greenhouses for winter Fodder growing

Sprouts and fodder are a magnificent way to feed hogs (as well as poultry!). But how do you do it at scale in the winter, when its too cold to sprout grains outside? One option is to move indoors, but that takes a lot of space and expensive climate control.  Another option is to invest tens of thousands of dollars in expensive commercial fodder systems. They work great but.. what small farm can afford to pay those prices? Our answer is much simpler and very cheap.  I only hope it works!

During the fall we developed an inexpensive fodder system based on hard plastic kiddie pools.  It has served us very well, performing perfectly (except for one fixable minor detail).  What you see here is the fall version of this setup... pools under draped plastic sitting on pallets, holes in the bottom for drainage and water timers set to fill the pool once a day quickly, then drain out.



The fall fodder system
For the curious, the one change we need to make is to place the holes around the outside edge, not across the bottom. If the bottom holes plug up for any reason, its a mess! you cant get to the holes to clear them.  This happened once. Our upgraded answer is to place the holes around the outside edge at the bottom so that they are accessible for cleaning.

Back on point... what to do for winter. As the rains come here in southern oregon... the draped plastic just creates a nifty duck pond over the grain!  The cooler weather is made worse by the rain water cooling the grain and blocking the suns heat.  So now we need a way to heat the grain from the sun and keep the rain out. a mini greenhouse! Modeled after the hoops often placed over garden boxes, this seemed a great approach.

Version 1 didnt work out so well... I tried to use regular 1/2 inch PVC, with Ts placed around it to allow for uprights, then bent into a 5 foot circle. This would have fit right inside the pool while allowing easy uprights for hoops.

First attempt didnt work out well at all... broke on bending into a circle.

The problem was that while the pip would bend into a circle... the Ts were not strong enough and popped in two. Other than a great math lessons on circles, this one didnt serve for anything other than a straight line. 

On to version 2... CPVC! Much thinner and flexible. Hopefully overcoming the stiffness of half inch PVC.  
Second attempt made it into a circle, barely, with a Tee-Pee over it.
Again.. failure. Yes the pipe bent easier but the CPVC Ts were even weaker and sook split from the constant pressure of the curve.  We switched to a Tee-Pee design instead of hoops to lower the pressure from the bent uprights, but still no go.  Not strong enough. 

Version 3 was back to half inch, but with no Ts... only 2 couplers, and snap on "T"s to hold uprights. Much better! The couplers held fine, and the snap on Ts resolved the need for so many weak spots.  Getting closer, but still didnt like the difficulty building with all the stress, glue, and pressure. 


Third attempt was actually useable, almost.

I had chosen to go with this design, BUT... while in the store collecting supplies, a new idea hit me... flexible pipe! A roll of black plastic utility pip caught my eye. Yes! light, cheap, flexible, yet strong enough for this application.  an hour or so of toying with different connection options and we have a new plan!

Version 4, based on cheap plastic utility pipe rolls, snap on Ts, and hoop tops of the same pipe worked perfectly! Within an hour of building time we produced the first fully functional prototype.  It fits OVER the pool, is strong enough yet light and easy to lift and present a better angle to collect heat from the sun than a Tee-Pee design. Perfect!


Fourth attempt worked well!
The final product worked well. within a couple hours the daytime sun had raised the interior temp by at least 20 degrees! It was a warm steamy tropical sprouting environment on a chilly day. A gust of wind came by later and blew away an empty pool, but the hoop top stayed put. 

Now we will finish the rest of the pools, and hopefully document the final building process as an available E-Book that you can use yourself. 


posted from Bloggeroid

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