Tony Hague wrote:I find this discussion slightly surprising. We are talking about cordon tomatoes here are we ? I have a greenhouse of similar size, and fit in ten plants on one side. I use a ring culture method, with the plants maybe 14" apart, in two slightly staggered rows. I guess this is the upper limit, but I haven't had fungal problems except for botrytis late in the year, which is pretty common I guess. I do have an auto vent, and have a hook to hold the door ajar in hot weather. The advice of 10 degrees minimum for tomatoes seems pretty unanimous. One more thing - I used a sulphur candle one year, never again. Sets all metal parts and fittings corroding, including the vent opener !
Thank you so much for that note of caution re sulphur candles! I was considering going that far, but won't now. To be honest I've been growing tomatoes for 40 years, and it hasn't been until this last two years that I've had a problem, leading me to the conclusion that it lingered over the winter. Do you ring culture into greenhouse soil or into grow bags? I'm not sure how I would fit 10 into an 8x2 space, it's like a jungle mid summer with only 6 plants, but staggering is definitely an option. I do have 2 auto vents, a ground level louvre and a roof one, but being auto they close overnight. I might try propping them open overnight when the 10 degrees is met.