Building a Greenhouse

I grew up living next to my grandparents and spent many days working side by side, starting seeds and transplanting plants, with my grandfather in his greenhouse. It was a fairly good size with a stone foundation and glass panels. It was attached to his garage which had a furnace to heat the garage and greenhouse and had running water and electricity. I have many fond memories of spending afternoons with my grandfather in his greenhouse.

Now that I am older I often dreamt of having my own greenhouse so I could start seedlings in the spring, extend the season in the fall and possibly relive some of those childhood memories. For several years I looked into purchasing a kit but was discouraged by the high prices and cheap plastic panels they came with so I decided to do some research and design and build my own.

Three years ago, after spending countless hours deciding what size to build, what materials to use and what accessories to add, I finally built my greenhouse.

My original plan was to build the greenhouse out of cedar, but because this was my first attempt I didn't want to invest too much into something that might not be exactly what I wanted, so I decided to use pine 2 x 3's for the framing and 6 mil greenhouse plastic for the covering. The entire cost for the 6'-10" x 8' greenhouse the was less than $150.00 including all the hardware.

Framed greenhouse.

Covered greenhouse.

The greenhouse has two work benches, the one on the south wall is 24" high and the one on the north wall is 36" high. There is a vent/window on the wall opposite the door. The floor is covered with landscape fabric which seems to work well for now. The late spring sun can really raise the temperature inside, so I have added an automatic vent opener to the window this year. The vent opener can be adjusted to open and maintain a constant temperature inside. It has been working perfectly and has saved me on several occasions when I would have forgotten to open the vent in the afternoon or close it at night when the temps dip below 50 degrees.

This greenhouse has held up remarkably well considering the framing is untreated and unpainted pine. The greenhouse film is rated for 5 years and hasn't cracked, ripped or yellowed despite being exposed to the northeast bitterly cold and snowy winters.

This fall I am planning on building a new greenhouse. It will be a more permanent one so I am going to construct it out of 2 x 4 cedar. I am planning on making a larger one- probably 8' x 12'. It will have a crushed stone and paver floor, running water with irrigation system, more vents, shade screens and possibly a propane heater. I am also considering using polycarbonate panels instead of the 6 mil greenhouse film to try and better control heat loss in the winter.

****** Update 9/29/12 - Greenhouse Plans are now available! ****** 

* ***Many sizes available from 6'x6' to 8'x16'! ****

You can purchase them from my ETSY store

and they are available in both PDF and Print.

     

Planting by the Phases of the Moon

One of the most interesting, and controversial, techniques I have come across while studying biodynamic gardening is the planting of seeds by the phases of the moon. It's the concept that the lunar gravitational pull has an effect on the germination of seeds and the roots of transplants. I have often started the same variety of seeds at different times only to have one batch germinate almost immediately and the other take up to 2 weeks to germinate.  I never understood why until I read about the influence the gravitational forces of the moon has on plants.

The basic concept is you start seeds 2 days before a new moon, in the first 7 days after the new moon the lunar forces increase root and leaf growth, in the second 7 days the lunar forces increase the leaf growth rate. On the full moon you should transplant your seedlings, then in the next 7 days the lunar forces increase root growth and in the next 7 days there is a decrease (resting period) in root and leaf growth. With the next new moon the cycle starts all over again.

Cucumber seedling planted 5 days ago following the Biodynamic Planting Guide and Calendar.

The book, How to Grow More Vegetables by John Jeavons describes in greater detail the process of planting by the phases of the moon. There is also a Biodynamic Planting Guide and Calendar which you can purchase from The Biodynamic Farming and Gardening Association which really goes into great detail describing the forces of the moon, starts and planets. It also gives you a daily calendar that tells you which seeds to plant on which days breaking it down by Leaf, Fruit, Root and Flower categories. This is my first year using the Planting Guide and Calendar and the results have been remarkable!

Starting seeds with soil blocks

Pepper seedling in 3/4" soil block

A few years back  I started using soil blocks for starting seeds after becoming discouraged by the low germination rates I was getting using plastic propagation trays. Soil blocks are easy to make, eliminate the need to buy pots, take up lees space and provide extremely high germination rates!

3/4" and 1-1/2" soil block makers

Soil block makers come in 3 different sizes - 3/4", 1-1/2" and 4". You can make your own soil mix or purchase specific soil block mixes. Smaller seeds are started in the 3/4" soil blocks.When the seedlings germinate and the roots start to grow out of the blocks you "block up" to the next size. The 1-1/2" maker has 3/4" square dibbles to allow the 3/4" blocks fit perfectly into them.

1-1/2" and 3/4" soil blocks

The compact soil blocks stay together so they are easy to handle. The roots will grow to the outside edges of the blocks and develope a healthy root system. In the photo above you can see the roots of the cucumber in the 3/4" block on the right coming out at the bottom. The soil blocks can be placed directly on the heating mats, but I use recycled lettuce containers from the grocery store. Each container holds 80 - 3/4" blocks and creates a mini-greenhouse preventing the blocks from drying out too quickly.

Recycled lettuce containers, each holds 80 - 3/4" soil blocks

When planting in the soil blocks, I place the seed in the dimple created by the block maker and tap each seed in making sure it has good surface contact. I don't cover with a layer of soil becasue the seeds seem to germinate better when exposed to air. I get 80%  to 100% germination rates using this method. Seeds seem to germinat quicker - the photo below of cucmber seeds was taken 2 days after planting, every seed germinated (the 2 blocks in the lower right hand corner weren't planted).

Cucumber seedling in 3/4" soil block

Johnny's Seeds has a great video that explains soil block makers in more detail and shows you how to use them. Another excellent resource is Eliot Coleman's book The New Organic Grower. Eliot goes into great detail explaining how to plant in soil blocks, why they work so well and even shows you how to make your own soil block mix. The New Organic Grower has become one of my most valuable tools in organic gardening.