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Growing Tomatoes

Tomato growth -- heat or light

15 years ago

I was thinking about growing tomatoes where the days are long, 16-20 hours of sunlight, and the effect this has on days to maturity. I know corn is rated by heat units, days above a certain temperature and wondered if tomatoes have a similar reaction. Basically, do longer days affect days to maturity and if there is a benefit to longer days is there a minimum temperature needed to see it. The trade off for longer days is a shorter season.

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Comments (5)

dave_f1 SC, USDA Zone 8a
15 years ago
I'd think it would mainly depend on the heat unit accumulation. Maybe light intensity has an effect on physiology also. At your northern latitude, the longer days are probably counteracted by alot less light intensity with the lower sun angle. I'm curious to read what others think.
Dan _Staley (5b Sunset 2B AHS 7)
15 years ago
Light intensity certainly has an effect on physiology, as does day length, degree days, soil temp, etc.

I'd ensure the soil stays as warm as possible as one of the keys to growing toms up there. I honestly don't know how much shorter a 'days to maturity' might be up there, but you may want to ask the dope growers or the folks in Palmer/Mat-Su what effect they get on their broccoli/cauliflower/cole 'days to maturity' in the field. If I were to guess I'd say the 'days to maturity' might lessen by 10-15%, but that's a guess.

Dan
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dave_f1 SC, USDA Zone 8a
15 years ago
I'm wondering if a greenhouse tomato grower would have some info about whether daylength affects 'days-to-maturity'. If the same variety is grown during winter days and also during spring/summer days, with similar greenhouse temps, would the day's to maturity be different?

I did learn that tomatoes are essentially day-neutral...it can flower and fruit at most any daylength.

I believe a 14-hr photoperiod is considered ideal for greenhouse production of tomatoes. Maybe too much more than that will adversely affect fruit set/growth?

I'd like to know more about it.
Dan _Staley (5b Sunset 2B AHS 7)
15 years ago
It's an interesting question - do tomatoes need to do dark respiration for some cellular functions? Being a tropical plant, you'd think that a set photoperiod would be ideal, but there are so many varieties out there...hmmm...I'd like to know more too.

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eaglesgarden
15 years ago
I am trying a variety called "Sub-Arctic Plenty". You might want to look into it. It is supposed to fruit set at much lower temps.

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