Michael: Where are you located? Well the ventilation system is all natural. I open up the north and south doors and the sides pull up the four feet. We live on a hill and we always have a breeze. I haven't run into many disease problems. I thought I had some early blight started, but I sprayed with copper and everything stopped. It was either the blight or a magnesium deficiency. I sprayed with epson salt too. I am going to put up a third tunnel like the ones in the pictures sometime early in the spring. I am also working on plans for two smaller movable ones. I would load them with broccoli and cauliflower then move them and load them up with squash and pickling cucumbers. That fall I would replant the outside with carrots and move the tunnel back then we could overwinter them. Then in the spring planted green building, I would replant spinach, chard, kale?, lettuce and other cold tolerant crops. I love working in the tunnels in the late fall or early spring. I had to put a coat hook up this year. Ok, it was just a screw, but I did hold my coat. I got too hot working. Big plans for the tunnels, I hope the pan out! Here is a picture of the sides pulled up.

The extra cost of film isn't much compared to payback. I used to have only one layer on a 20x96 and 30x96 and was somewhat satisfied but after hearing all the facts on temp. benefits (which I don't have at my disposal) I readily recovered both with not just 2 layers but inner light dispersing,anti drip layer. An extension agent doing tomato research claimed that the light dispersing layer caused tomatoes to grow so well that it caused a potassium deficiency. Also the non-drip film seems to keep leaf mold incidence down. I don't over-winter any crops but usually heat for all of March and most of April, after planting and often again for the end of October and November. I tried also using inner frame with fabric covering and also covering over short wire hoops but without circulation fan air movement I always lost plants at "Cold Spots". In zone 4 I'd be conserving every last bit of heat possible with the double outer cover. Just my opinion.

Most of you are throwing out names of mixed det. and Indt. varieties like they go well together. The one thing I'd suggest is to stick to one type or the other. I use stringline support and prefer only Indt varieties inside my tunnels. I plant oner 200 mixed Indt varieties; most plants are hybrids, most number of different varieties are heirlooms. I like Big Beef as my wookhorse variety and wish I had not bought so many expensive Trust seeds 7 years ago. I like Geronimo and this year Caimen stood out with even larger fruit than many others. You might also try First Prize, Country Taste, Tough Boy and Rebelski as well as a number of better pink beafsteaks like Brandy Boy or BrandyMaster. This year my biggest moneymakers were my cherry/grape types. Mixem-up and you can't go wrong. I've picked them non-stop from mid-May thru the end of Nov.-thus the recommendation to stay with Indeterminate varieties in a tunnel.

Galiano, are you looking at the pic above or below my 'unknown beefsteak' comment? The one above is brandywine, but the one below (the unknown) actually has regular leaves, which might not be clear from the pic. Just have them in regular old triple mix. My 'seedlings' were large when planted (if I plant small seedlings, they just don't have enough time to produce a lot of fruit in my short season). I use dilute MG from time to time, some high P initially to help roots, then some high N to get the plants going a bit, then more high P later to promote flowering. I apply a lot less than the directions suggest. Also mulched this year for the first time. Other than that, we have not had a lot of rain so I have been able to control the water, and despite the cool weather there has been a fair bit of sun. However, despite the attractive plants, fruits are still at least 2 to 3 weeks behind where they normally are. Star stuff, the typically relied upon last frost date is around May 24 (which coincides with one of our statutory holiday weekends), but for the last few years the weather has been far too cold to plant on that date. We had frost near the end of May this year, and in the first week of June last year. So, end of the first week of June was when plants went in the ground for me. Won't get frost again until end of Sept. or maybe October, but I have found that fruits that I harvest after the end of August tend to be a bit sub-par in terms of texture and flavour. With ideal conditions I would usually be harvesting great fruit from the middle of July to the end of August, with a few outliers coming early, and plenty of second-rate fruits in sept and into oct. Humidity finally starting to show up now, along with some warmer nights, and a few more months of this should help the fruit grow nice and big. Of course that weather tends to wreak a bit of havoc on the foliage, but thats ok as long as I get to start eating tomatoes soon.