Greenhouse Adventures - squeezing every penny till it screams.

By Jeanine of Local Sustainable Food Garden

Submersible well pumps and greenhouses; two seemingly unrelated objects do really have a lot in common – at least here on the Farmlet.

I have tried a couple of different greenhouses and each time that we had the handful of prolonged freezing days here that required heat…. I chickened out.  I just cannot make myself provide heat for a few trays of spinach and assorted seedlings. 

We are also on city water here (yuck) and this year my birthday present was a well.  No, in my book that is not like getting a vacuum cleaner for my birthday.  My husband knows not to come near me with diamonds and pearls – give me buckets, shovels, piles of composted poo and I am a happy camper.  So now I have the well that has long been part of my self-sustainability plan and it needs a house to go over it to protect it from freezing.

I have had a few wells in my day and the pump house has always been a small dark dingy affair that gets stuffed with insulation and, when there are more than two days of freezing weather, a light bulb is added.  Spiders, snakes, mice and other critters love it.  My own personal light bulb went on while pondering this and Voila! – Put a greenhouse over the pump!  The passive heat from the greenhouse will heat the pump for all but the most prolonged freezing periods and when I do have to provide supplemental heat I’m getting two-for-one; heat for greenhouse and pump. 

The greenhouse was ordered and has arrived.  Ominous looking box full of parts but three hours later and a minimal amount of cursing it was fully assembled.  The weed barrier floor is in place and the first of three 50 gallon black water barrels has been installed.  The first one has been filled with goldfish and topped off with a few floating plants.  In theory the water barrels will provide passive solar heat, and the fish-poo water will provide nutrients for watering plants.  Also the greenhouse can be anchored to the 50 gallon barrels to help keep it from flying away during wind storms (that has happened here in the past).

The area that was selected for the greenhouse & well is shaded during the summer by deciduous trees so after leaf drop it will receive sun all day.  This should eliminate having to cool it during the summer.  This same area is also fairly well protected from wind and with the addition of the greenhouse a kind of micro climate is created right around the outside of the green house; this area has already been planted  with spinach, cress and something else (I forgot what already).  A worm bin is planned, to be installed under the seedling benches to catch run off dripping from the seedling trays.  The runoff (tea) from the worm bin can be used as additional food for plants both inside and out.

I collected most of these ideas from City Roots, an urban farm in Columbia, South Carolina.  Of course my set up will not be as elaborate as theirs.  They are growing Tilapia, micro-greens, and herbs in a fantastic greenhouse in the city.  They also have a year round garden and chickens.  They host a large number of school groups and are hospitable to anyone who just wants to drop by to look around.  What a great resource for urban folks!

So, I believe that I have multi-purposed this thing to death but if anyone has suggestions for additional functions this setup could serve I would love to hear them.  I like to squeeze every penny till it screams.

Update Dec. 1, 2011 – Since first writing this a couple of weeks ago I have learned a few things:

 Adding fish to the unfiltered well water in barrels made for a black gooey mess.  The fish poo and food combined with the iron and manganese in the unfiltered well water and became swampy smelling and almost solid black.  From what I understand this is not necessarily harmful to fish or plants but it is unpleasant to me so the fish went out to the goldfish pond where the same water and fish do not seem to have this reaction. 

Despite two 50 gallon barrels (painted black) of water and I’m not sure how many blocks of pavers and concrete blocks for thermal mass the greenhouse still registers only a degree or two warmer than the outside temperature at night.  I still have a third 50 gallon barrel to add and am going to add bubble wrap to some areas that I suspect of heat loss.

I do have various types of lettuce and some sage and basil coming up in the greenhouse and they look great.  Three other large basil plants and a pathetic Meyer Lemon that I have been dragging along for three years are doing very well in their new greenhouse home.  So the process of learning continues and I welcome any inputs and will continue to share my failures and hopefully a few successes with you as they occur.

Oh and BTW, if you want your Navel Orange tree to benefit from the greenhouse you have to actually put it INSIDE instead of leaving outside NEXT to the greenhouse like I did.