Create a Zone 8 Microclimate in Zone 5: Temperature Data

Create a Zone 8 Microclimate in Zone 5: Temperature Data

Does each layer of protection in the winter garden effectively move the garden 1 1/2 zones to the south? Today I look at temperature data to find out.

“Four Season Harvest” by Eliot Coleman:
“The Winter Harvest Handbook” by Eliot Coleman:
“The Year-Round Vegetable Gardener” by Niki Jabour:
6 mil Greenhouse Plastic:

If you shop on Amazon, you can support OYR simply by clicking this link (bookmark it too) before shopping:

Crops we’re growing now for a winter harvest:

Under One Layer of Protection
Dandelion Greens
French Sorrel
Good King Henry
Mustard Greens
Perpetual Spinach
Sea Kale
Tree Collards

Two Layers of Protection
Dandelion Greens
Dinosaur Kale
Egyptian Walking Onions
Garlic Chives
Georgia Collards
Giant Red Mustard Greens
Italian Dandelion Greens
Lettuce (Romaine)
Mustard Greens
Perpetual Spinach
Fordhook Giant Swiss Chard
Red Veined Sorrel
Tree Collards
Vates Kale

OYR is all about growing a lot of food on a little land using sustainable organic methods, while keeping costs and labor at a minimum. Emphasis is placed on improving soil quality with compost and mulch. No store-bought fertilizers, soil amendments, pesticides, compost activators, etc. are used.


  1. Roop Singh on January 6, 2022 at 3:46 pm

    I love this channel, I find it to be the best frugal/organic gardening channel on youtube, perhaps with california gardener coming second. it’s amazing what you’ve done on a small budget and your focus on soil. please know it’s had quite the impact on me. i use free local resources to build soil (leaves, horse manure) and garden in raised beds in my terraced yard. our soil was once complete clay which grass and weeds wouldn’t grow in. now i have handfuls of worms and nice humus.

    of particular praise, i really like your calm explanation that are very easy to understand and how you test methods scientifically, adopting some like the hoop house and casting away others like compost turning and comfrey tea.

    amazing work, please keep it up, you truly are a benefit to gardeners everywhere!

  2. Rafs Kitchen Garden on January 6, 2022 at 3:48 pm

    Hi Patrick, Thanks for all the useful data, It is impressive how well it keeps temperatures without any heating source, do you get any problems with condensation ?

  3. Morning Glory Glorya on January 6, 2022 at 3:49 pm

    Another informative video. Thank you 🙂

  4. B Charron on January 6, 2022 at 3:51 pm

    ***Have you tried combining geothermal heating with hoop houses, and is so how did the results fair***

  5. Prairie Plantgirl on January 6, 2022 at 3:52 pm

    I’m considering putting up an unheated greenhouse/hoop house and Custom Garden Solutions sent me to your site. This is the best information I have found about the effects of an unheated structure like this. I’m zone 3 (2b) so I’m guessing with double structure I might be able to achieve around zone 5. I would love to be able to extend the season and possibly overwinter things that just can’t be left out here. I’ll be subbing and lurking around on more of these older videos.

  6. Rees Riddoch on January 6, 2022 at 3:53 pm

    How thick are your inside plastic sheets? How did you make your inside cold frame?

  7. Southpaw Davey urban farm. on January 6, 2022 at 3:53 pm

    Super data. Looks like it works great.

  8. GippyWhite on January 6, 2022 at 3:54 pm

    Fascinating infomation! Thank you for tracking it with such detail. And Oscar is the cutest rascal I’ve ever seen! LOL! Are you going to keep tracking everything for the next few months? Since it’s supposed to get a lot colder from now on, I was just wondering what will be still growing. Love the videos and much love to Oscar!

  9. Rose M on January 6, 2022 at 3:56 pm

    what year did you come out? have lived here for 35years this coming Monday and ever year I say the same thing! time to move! Ha ha

  10. Kate Sickles on January 6, 2022 at 3:56 pm


  11. Dale Calder on January 6, 2022 at 3:57 pm

    That was very interesting Patrick and gave me more hope for my artichokes that are under a cold frame in the hoop house. So far our coldest temperature has been -14C. We usually get at least one cold snap down to -20C or -22C or so.

  12. Rose M on January 6, 2022 at 3:57 pm

    have you ever thought of moving to Arizona? yes it’s very hot here with a little know how you can grow all year long! give it some thought!?!

  13. BrokerBarbara on January 6, 2022 at 3:58 pm

    Perhaps hanging a couple of bulbs to provide a little heat?

  14. wildchook (Mary) on January 6, 2022 at 3:59 pm

    I love the new hoop house. Good to see you continue to grow food in winter. I love the new setup.

  15. Suzanne Ramoundos on January 6, 2022 at 3:59 pm

    Great that you quantified the experiment.  One year we put up a greenhouse, the cheap kind you get at Lowes and the zippers froze shut.  Its hard to keep up with crazy weather changes, and forget about it you are working.  In the spring, we would try to leave the windows open before leaving for work…bad idea…winds would come and despite it being well secured or so we thought, basically rip everything to shreds.   But with the thermally activated vents that may be a really good idea.   Still everything looks so great.  Glad you are being rewarded for all the hard work.

  16. Land Outdoors on January 6, 2022 at 3:59 pm

    It would be interesting to see if adding some thermal mass into the cold frames would help regulated the fluctuations in temps on those cold overcast days. just a coffee can painted black with some sand or water might even be enough. It does seem like you don’t even need it based on the numbers you are getting, but it would still be interesting to see if it had any added benefit.

  17. Silvija Mažuolienė on January 6, 2022 at 4:00 pm

    Thank you! I am in zone 5 and started gardening. It’s winter now but by next winter I hope to have just what you showed – whole year garden. It’s inspiring to see that this is posible. Nice cat! 🙂

  18. Brandon Marshall on January 6, 2022 at 4:05 pm

    That is very impressive! We are in zone 8, nice to not have do all of that here. Maybe I COULD grow some tropical pants here then, in a hoop house….one day…

  19. Hello My Garden on January 6, 2022 at 4:05 pm

    We enjoyed seeing the temperature data!

  20. ClintL63 on January 6, 2022 at 4:06 pm

    You have me thinking of a greenhouse heated by a rocket stove in the evenings; zone 5 Northern Lower Michigan

  21. lmtada on January 6, 2022 at 4:06 pm

    Excellent data. Thank you. Edmonton, Alberta.

  22. In the garden with Grandpa and Grandma on January 6, 2022 at 4:07 pm

    Great info and results Patrick. What are you using for measurements?


  23. Carissa H on January 6, 2022 at 4:08 pm

    Thank you for all these great videos! I’ve enjoyed them so much and appreciate the temperature data.

  24. Dritan Bega on January 6, 2022 at 4:09 pm

    I am happy with your success. Somehow I know that you eventually will put an air vent, in the hoop house, and I am eager to know what solutions will you chose. . ?Keep prospering

  25. Eleanor O'Connor on January 6, 2022 at 4:09 pm

    Merry Christmas Patrick and Oscar, looking forward to what you will teach us and what new you will plant for 2018. Your videos are so informative and I watch them over and over again and learn something new each time. Have a happy and healthy New Year, from one gardener to another.

  26. SpartanMonkee on January 6, 2022 at 4:11 pm

    Great data! It would be interesting to see if a second layer on the roof, creating an insulating layer, would free you from having to have the cold frames within the greenhouse.

  27. Achilleus Petreas on January 6, 2022 at 4:11 pm

    As great as this protection is (I’m doing it myself this year, so thank you!) it is not at all accurate and a grave generalization of zones. Zones are about the average extreme minimum winter temperature per year…not average highs and lows during the winter. That can vary extremely within the same zone. I live an hour north of Detroit…which is zone 6b/7a. The average winter temps are defiantly not what you suggest, which is more common in a zone 6b in the upper South. Plus…if it was 0F outside (which is the coldest of zone 7a) and it was 20F in the 2nd layer (the coldest of zone 9a), then it is only 2 zones warmer at the max. I love the work you’re doing, but I believe this is stretching it way too much…did you record any other temps during the winter?? I would love to know…

  28. Ashlee Hatten on January 6, 2022 at 4:12 pm

    Hahaha Oskar is hilarious

  29. Cate's Garden on January 6, 2022 at 4:12 pm

    Awesome stuff as always.

  30. Emerald Bren on January 6, 2022 at 4:15 pm

    awesome information Patrick as always….. with the size of your garden the next year’s project should be a completely covered garden with a retractable roof!!!!! have a great week mate.

  31. Veronica Be on January 6, 2022 at 4:17 pm

    How to grow mache, and is it cut and come again? I saw you cut the entire head, is it dead? can I seed it directly into the soil w/o covering in the harsh winter here in zone 5b and high 7000 feet, and dry. also claytonia or should Iwait until december or January or Feb to grow outside, or to grow them indoors? thanks.

  32. Logan Cook on January 6, 2022 at 4:18 pm

    The type of greenhouse can also play a major role in minimum temperatures. Last spring I built a lean-to type greenhouse which sits against an exterior south facing wall of my house. What I have notice this winter is that heat loss through the wall of our relatively older home actually heats the green house. Surprisingly the greenhouse will not experience freezing temperatures until the outside temperature is in the upper teens. The Lowest recorded temp this winter was 23 degrees Fahrenheit when the outside temp was zero. Eastern Washington, zone 6a.

  33. Lyle Vander Velde on January 6, 2022 at 4:19 pm

    wow Great data Great video

  34. D Lo Mack on January 6, 2022 at 4:19 pm

    Do you use a fan inside your greenhouse?

  35. Eleanor O'Connor on January 6, 2022 at 4:22 pm

    not to long ago you posted a video on how you covered the north side of your hoop house with some insulation, I can’t find that video and I wanted to know if that insulation came in sheets and how many sheets you used? I continually watch your videos over and over again. Keep up the good work and sharing your info with all us gardeners

  36. Rob Bob's Aquaponics & Backyard Farm on January 6, 2022 at 4:23 pm

    Am so glad I don’t have your climate Patrick. Then again I suppose you’re glad you don’t have the warm weather pest like our fruit flies 😀 😉
    Cheers mate.

  37. Mike on January 6, 2022 at 4:23 pm

    Your videos are always informative. Thanks for taking the time to share. I learn something new every time.

  38. Jewell Loveless on January 6, 2022 at 4:25 pm

    I’m late to the game, but I love your videos! So informative! And I love your kitty!! I’m getting a small greenhouse for Christmas, and your videos are exactly what I needed to feel more confident. Thank you!

  39. Michael Ball on January 6, 2022 at 4:26 pm

    That’s a lot of maths (math sorry) for one film Patrick! I’ve just uploaded a vid to show progress in the garden and the results of my trip to the brewery today. Whilst there I noticed some sacks full of a substance I didn’t recognise, the brewer said it was waste hops and I was welcome to take as much away as I liked so I brought home half a dozen sacks. The only problem now is that I need to find more pallets to make another compost bin with to deal with the hops. Have you ever used hops?

  40. Elyse Joseph on January 6, 2022 at 4:27 pm

    Well done Patrick!!!

  41. A Roybal on January 6, 2022 at 4:27 pm

    Hi! Thanks for the amazing videos! I live in zone 6A and want to do a hoop house. I am confused as to what plastic/coverings I should use though. Any recommendations?

  42. Paula Beattie on January 6, 2022 at 4:28 pm

    That was excellent information, thank you.

  43. matermark on January 6, 2022 at 4:29 pm

    What’s the most snow depth the hoophouse survived? I still keep wanting to build something in the yard, but I had a CoverIt garage with a heavy duty polyethylene covering over steel tubing, I think 2.25" with some 2.5" steel fittings, and it had a clear section 6 to 8 feet wide down the middle for light. I did a lot of mods, plug-in electricity & conduit, shop lights, etc., even added foil-covered insulation panels (4×8, Celotex?) but we had heavy snow over a few days I couldn’t get there and it caved in. They may have gone out of business, but the point is 2.25" galvanized steel tubing must be 10x stronger than pvc and it still caved in, the tubing a mangled mess…

  44. Angie Swyers on January 6, 2022 at 4:31 pm

    So have a house inside a house to be able to get your greens to grow in winter.. I am in st louis. mo Alberta Sent me to your page.. I have 1000 sq foot Hoop house with double lair / Heater If i want to burn wood. But this past week my swiss chard froze.. And I moved the growing to the inside basement 1300 sq foot Lows of 57f .. I will be trying the greenhouse in a greenhouse this weekend.. Too much growing in side. Like 700 tomato 700 pepper plants, And I am getting sick of buying light.. 100 light 200 bulbs.. talk about the power bill going up.. lol

  45. Poppy B. on January 6, 2022 at 4:32 pm

    Excellent Patrick, the greenhouse and coldframes are producing the results!! The temps are spot on as well. Here in zone 8, our highs are going to be low to mid 50s’/20s’ and 30s’ for lows the next few days.

  46. Felicia Follum on January 6, 2022 at 4:35 pm

    this is amazing! I think I live in Zone 5.

  47. Healthy Life Farm on January 6, 2022 at 4:38 pm

    Love your charts Patrick ~ great information to know! I didn’t bother growing in my sunroom this year just not enough sun. I will be putting a few smaller version greenhouses mainly for the spring to help with the early spring/summer white butterflies and other garden pests. It is awesome you still can harvest vegetables in your zone this time of the year. Take Care, Peaches

  48. Ree Purpose on January 6, 2022 at 4:40 pm

    I wondered if it would be worth trying to grow outside in the winter. Thank you for such detailed videos. I always learn alot.

  49. ROWEBOT on January 6, 2022 at 4:42 pm

    Awesome video, loves the charts. I find myself wondering how the temperatures would be affected by incorporating some variable insulation. It is obvious that more than enough energy comes in during the day, but too much is leaving at night. What you really need are roll up style blinds made of reflective insulating mat. Those could be automated as well to roll down at night. This should increase minimum temperatures quite a bit.

  50. Laura M. on January 6, 2022 at 4:44 pm

    AWESOME!! nice cat…

Leave a Comment