The Growhaus II, Part I

We first addressed the small experimental Growhaus I© in previous articles. With learning points we have constructed Growhaus II ©.  The goal of this design is a perpetual underground watering system, a hip level walkway to the raised bed for ease of gardening, two growing beds, a ventilation system for summer heat venting, plus a long term natural underground layered fertilizer. Lastly it is constructed for under $350.00-to $500.00, not counting your labors.

The first concern is location for the plants you intend to grow. Not all plants need to be in the blazing sunshine, some, such as many herbs, prefer shady nooks.  Therefore in some instances you may construct your Growhaus under a tree, or on the north side of a building. There does exist “shade” covers that could be employed too in case you change your growing needs. 

This design is a seasonal extender with one layer of a “plastic” covering that will keep your precious early spring (starter plants) safe down to brief 20(o) F temperature. Further protection may be gained by using two layers of plastic covering and an additional “hoop” of row cover inside the Growhaus © beds-perhaps adding soil heating cables if you want to become aggressive when the weatherman says it will drop to zero F tonight.

However, I look at this Growhaus© as a seasonal extender with which you will be thrilled to use-and it is inexpensive compared with a comparable $3,000.00 cost for a basic plastic commercial hoop house with no underground preparation.

I want to add at this time that the first passive “Solar Greenhouse” I put up was designed for –30(o) F, primarily as a seed starter with some growing beds inside.  This is an entirely different concept, more laborious and costly  ($2,800.00) but when we get around to discussing it I am sure you will want one too.   It will be another two years, or more before I build the in-garden  “mini solar greenhouse”, so in the meantime for the avid, serous and determined gardener I suggest a serious consideration of the Growhaus II © design. I do want to construct my long awaited Austrian Bee House for my gardens, plus a new garage structure for my planned new tractor; hence delays in basic garden plans. 

With experimentation I now believe that growing plants are happier with layered fertilized soil and manures down to two feet.  This makes it easier for you than mixing tons of soil and composts for the ultimate growing medium.  Plants have roots and as we discussed a year ago (see archives) these roots fan out along the surface to gain nutrient feeding in the top foot or so of soil.  The leaves fall, the master gardener earthworms pull the nutrients down to the shallow roots.  The deeper roots continually search out water and minerals.

Now that you have a Growhaus© location in mind, consider additional Growhauses© locations for the future.  I am very keen on the underground watering system.  This entails roof water run off to the 4” slotted diameter covered plastic leach lines, so every shower of rain is collected and concentrated to your garden beds.  In addition you can collect water in a thousand gallon and larger tanks for backup water in dry and draught conditions.  Global catastrophic weather prediction and such Armageddon forecasts-true or not, does not matter except in talk.  But what does matter is that our planet has always been weather driven by the sun and most notably is the 11-year sun cycle.  We are now entering back into an active sun cycle, and based on observances of sun spot activity for the past 400 years it will influence draught conditions for the immediate future.

This means that you have to consider water needs to grow food/herbs/fruit.  To let the roof water run down the gutters into the unused spaces of the useless lawns is plainly lacking in common sense. If you are dependent on the city water supply consider they will have water shut off hours when the reservoirs dry up and the city water is costly. For the health conscious consider that it often polluted with chemicals, recycled wastewater and the list goes on and on.

If you have a water well- good- that water is cleaner and will be used for the house and maybe starter plants.  But, again, you cannot water a garden adequately with a 6” well 300 feet deep; there is only so much you can pump at a time.  OK! Back to the archives and read about how much water you can collect off a roof, per square foot.

Perhaps a pond is in your mind.  Ponds can dry out in draughts.  During the wet sun cycle my pond is full and I have the option of plumping water.  However the dry season is iffy.  My current thinking is the water tank storage.  I have one 2,000-gallon tank in the ground and collecting water.  I have another 3,000-gallon tank ready to bury this fall.  We bury them in ground, as they will freeze otherwise.  This water can be gravity fed to the garden, or Growhaus © underground pipes by gravity feed in some cases, pumping in others.

Since I am on the topic of water, and I am conserving even the nightly dew on the Growhaus© plastic cover as it runs down into the bottom rain gutters and is channeled around to the underground raised collector spouts.  Notice this in the attached pictures in the series completion.   Waste Not-Want Not!  I will restate that our Australian friends, just to live must have major cisterns to save water for private household use, much less gardens.  These 15,000-gallon cisterns seem adequate for that dry, barren desert community (Think Colorado and the dry North American west.) Most cisterns are already dry.

Let’s get started. After selection of your site it does not really matter if the long axis is north or south.  I favor east and west, yet many of my plantings are north and south.  They all do well.  This Growhaus II © is 10‘ wide and 20’ long and divided in the center long axis with a 2’ wide walk way.  This leaves a 4’x20’ growing bed on each side. The pictures show step down into the Growhaus II © allowing the gardener to reach at hip height his or her favorite plants and easily clean up weeds etc.   In comparison of the depth of the walkway (hip deep) is optional.  The younger gardener with out the creaky bones of older years does not need a deep walkway, but in later years I find the hip deep one most convenient.  The young gardener could even just have a central path and do a lot of kneeling and may gain a small bit of more garden space.

I think it advisable to locate the Growhaus II© on a level plot.  Unfortunately this one was on a downgrade.  I had originally intended a 30’ length, but as I started at the high end of the grade and I moved down the slope I had to add more and more higher walls.  This entailed more and more soil and composts to be trucked in.  Also higher walls approaching 3’ high are unstable and require better braces and of course more money and labor. Treated lumber wood screws are best for holding the mass together when it becomes bigger and bigger.

The level ground construction would be started just like the Growhaus I© in the archives -removing the topsoil off the first bed and enriching the poorer soil underneath for another foot deep.  A layer of hay is placed on top this under enriched bed. This hay layer is for the earthworms, the necessary component of your garden.

Then we can box it in with 2’x10’ planks.  I now have found that placing 4”X4” posts in the inside corners and the centerline to nail the planks makes for a stronger assembly.  You can cut off the posts at a later date.

A note of interest.  Treated planks and boards are no longer guaranteed for ground contact-the system is going to force you into using recycled plastic planks.  These will last apparently forever but they require more in line bracing, as they are thin.  If you still have treated lumber, rough-cut oak, hornbeam, or locust, (from a saw mill) paint it with several coats of Copper Brown or Copper Green wood preservative found in the paint section of the Big Box Store such as Lowes™. WEAR EYE PROTECTION and painters GLOVES!  WASH HANDS when finished.

Next, on top of the hay layer, lay in the slotted 4” slotted drainpipe, cover it with the white sock or it will fill up with soil.  Lay out two tubes the length of the bed.  Note that the pipes come together at the end into a center collection pipe.  So what you need at this point is the following: A run of (2) slotted pipes, a spool of leach line “sock”, two 90 degree elbows, one T coupling.  Space out evenly.

Now take the topsoil and cover the pipes, adding layers of manure and soil.  I use rabbit manure- see section in archives on raising rabbits for food and fertilizer.  It is NOT necessary to till the new bed.  Your very last top of the bed will be a mixture of topsoil, sand and composts, or commercial organic Miracle Grow garden SOIL, sold in Wal*Mart garden section to an inch deep.  This is sterilized and will suppress any weeds that naturally germinate, and you can start plants from seeds with little worry as the moisture comes “UP” from below and the beginning seed or baby plant quickly shoots a deep root looking for moisture.  Of course you can mist the seeds and plants too.  This will eliminate a major weed headache for a period of time but you must always be vigilant and catch the grasses that pop out from deep below or they will take hold and strangle out everything.

I would add another 2’x10’x10’ planking around, as you will be adding more and more composts through the years.

On top of the planking you will nail down with galvanized nails a 1’x6’x10’ treated board flat to make a platform edge to secure the cover of the greenhouse and support the guttering.

A major mistake I made in this construction was not doing the entire structure in one season.  Excuses aside, the bottom structure was completed and I left it uncovered for the winter.  So it rained, then froze and buckled one side in the walkway.  Unsightly to the critical eye, I bring this to your attention-If you cannot complete the entire Growhaus II© before winter- COVER it as best you can.

There is no sense in buying earthworms.  You can a lay a cardboard sheet flat on the ground, plank or such and every day turn it over and gather up a few worms.  Place them in the finished beds.  They will multiply faster than you think in that super enriched, manure soil.  You have to have earthworms.

The lead in picture is a side view of the 20’ length with summer planted foods.  Note the hoops and wood frame, which will be covered next week. The squash plants were overwhelmingly plentiful.

All this and more next week.

God Bless
COPYRIGHT: 2009, Back2theLand, Mark Steel.