Wednesday, March 18, 2009

The Beginnings of a Poly Tunnel

A few weeks ago I started to build the poly tunnel I have been think about since last spring. It was revised many times in my head up to this point so it is nice that it is coming into reality. I am making it out of 2x4 cedar for the base and 2x2x48 cedar balusters for the upper frame. My plan is to permanently attach the plastic to both ends and then attach the top piece with velcro. The velcro will make for easy access and will help with wind resistance. The plan is to have the one side of the velcro sewn onto the top piece of plastic and the other side of the velcro will be stapled onto the 2x2 frame. The completed poly tunnel will be approx. 36"Wx48"Lx31"H.

In retrospect I wish I made the roof form a peak at the top for better shedding of water and snow. I will however add a support down the center so it should not pool water very much. I guess a certain amount of pooling is inevitable no mater what the design is when working with plastic sheeting.

Now for the good part. After reading about all the hardy vegetables in the "Heirloom Vegetable Gardening" book, I have been searching for a good mix of things to grow this fall & winter in the coldframe & poly tunnel. Here is a list of what I am planning on growing and a short description of what they are:
  • Arugula - narrow leafed green with a peppery taste.
  • Corn Salad (Mache) - mild tasting leaves on plants that form a small rosette. can reportedly be harvest year round in my zone
  • Endive - forms a large frilly head, slight bitter taste
  • Chicory 'Sugarloaf' - produces a head of lettuce similar looking to romaine, mild taste that is sweetened by the cold
  • Radicchio - another head lettuce with a bitter taste. Used sparingly in salads or slightly grilled to sweeten
  • Mizuna - asian green with very finely cut foliage, vigorous grower.
  • Tatsoi - asian green the forms a flat rosette of drumstick shaped leaves, hardy.
  • Bok Choy - asian green that forms a vase shaped rosette. it has thick, crunchy stems and leaves that are treated like spinach.
  • Kale - any low growing kale will overwinter as a fall crop with protection. i am going to try 'Vates'.
  • Swiss Chard - a thicken stemmed green that can be harvest up to December. the stem can be eaten like celery.
  • Spinach - a hardy green that can be harvest most of the winter with protection.
  • China Rosa Radish - very hardy radish that will only grow bulbous roots in the fall. tapered like a carrot with rose coloured skin and white interior
  • Long Black Spanish Radish - also grown as a fall radish, produces tapered roots with black skin and white interior. can be dug in late fall and stored all winter, will stay rock hard until April.
  • Red Celery - a bit of a contradiction as I said I was not going to grow celery. this one is very hardy and produces red & green stems that are good for cooking. will be useful in the cold months for stocks & stews.
  • Tonda di Parigi Carrot - a very short carrot that is well suited for growing in a cold frame or poly tunnel.
  • Potato Onions (multiplying onion) - these are extremely hardy onions that multiply into bulbs a little bigger then a shallot. you can harvest green onions for most of the winter and harvest bulbs when they develop. i first saw these onions on Oklahomegrownveg Blog
As you can see there are many unknown or otherwise under utilized veggies to extend your season. I will be giving many of them a try this year and will start planting in August for fall/winter harvest. Almost all these varieties can be purchased for a little over a dollar at Baker Creek Seeds, Sand Hill Preservation Center & Territorial Seed for the red celery


  1. Once again, I'm impressed with your productivity. I can't wait to see this concept put into action. Reading your veggie list has reminded me of some varieties, like the bok choy, I might want to consider for a fall harvest. I'll just have to make sure to put them in at the right time. I would probably plant in August too without a cold frame since I'm down in zone 6, but I can never seem to get the timing right with my fall plantings.

  2. Sally - Timing can be tricky as I found last season with my poor results with my fall crops. I am going to follow the dates in 'Four-Season Harvest' by Eliot Coleman. I should have also mentioned that the coldframe and poly tunnel will be left open in August and will not be closed up until late sept/oct.

  3. I also built a poly tunnel and I'm excited to see what happens this winter. I agree with Dan, timing is very important. I have found that starting things a week before you should is best, then you're guaranteed that they'll be mature if you happen to have an early cold snap like we did last fall. If I had planted my carrots a week earlier they would have been much bigger!

  4. Oh how pretty. I love wooden structures in the garden. I'm too cheap though and have my tunnels held up by 9 gauge wire. I need to figure out how to keep them up with the snow. I think I need a brace in the long direction. I'm thinking I don't need to deal with this until fall. Though with the snow we have had recently, you never know.

  5. I got my entire collection from Territoral seeds, shipped promply and all my seeds germinated!

  6. Chiot's Run - Starting a week earlier sounds like a good idea. Last fall I started a month late and it was a disaster.

    Daphne - This was actually pretty inexpensive, about $35 for the lumber, not bad as it will last forever. I'm not sure how you could brace wire, I'll see if I can think something up that might help.

    lilegyptiangoddess - This will be the first time I have ordered from Territoral. I have heard good things thought.

  7. I cant wait to see your poly tunnel. This is new to me and exciting...

  8. Looks like another great garden structure in the makings. I use grow tunnels in my garden with very good results. My winter garden crops include:

    swiss chard
    parsnips (not covered)
    carrots (not covered)
    mache (corn salad)
    bunching onions

    I also grow multiplier onions - but not as a harvested winter crop, rather I overwinter it to grow on and mature in the following summer. I love them because they replenish themselves - just as my garlic and shallots do.

    I buy almost all of my seeds from Territorial. They are a fine company whose catalog is almost a sit down read in and of itself - the info it contains is excellent.

  9. Cool! I can't wait to see your tunnel when finished. I still haven't got mine done yet...rats! Oh well, it'll be at least 6 months before it's needed.


  10. Skeeter - I hope to have it done some time in April.

    DoubleD - Maybe I will try some bunching onions too. My plan is to grow a few of a lot of things so I can see what grows best here.

    EG - Mine is not done either. I would like to get it finished soon though so I can use it for growing some fast lettuces or get the tomatoes out sooner.

  11. Wow Dan...your planning your Fall/Winter garden already? I think your planning on competing with me this Fall, and so you're getting a head start....that's what it is! lol

  12. Wow, that is a major list of veggies. Unforchunatly I will not be able to do very much this year at my house. I will be gone all summer, doing this stuff on a farm that I will be interning at! This will be fun. Good luck with the construction!

  13. Dennis - Well you have the weather on your side so I'll need the head start, hehe.

    Zach - That will be a fun Internship, it will give you lots to blog about.

  14. That's a very nice start.

    I love cedar, it makes beautiful structures. Should be a very classy final product, can't wait to see it finished.