Molasses is not just sucrose, it contains many, many nutrients which is, I think, why it being quoted as being used as a foliar feed. What we call sugar (sucrose) contains none of those nutrients. I have just accessed some scholarly articles behind paywalls which came up in a google search and have checked a couple for you. They say that sucrose can indeed be absorbed from a diluted spray on leaves (root intake is insigniificant) but that it didn't improve the growth rate of (in this case tomatoes) plants already growing in optimal conditions, so you will not improve your crop by doing this. It did help with those grown in low light, because the plants couldn't produce enough of their own by photosynthesis. The conclusion was that it may be of benefit when growing commercial tomato crops in winter under glass in northern areas.
My conclusion is that home gardeners using (white) sugar solution will see no noticeable benefit and would be better off using seaweed spray or obtaining and diluting actual raw molasses (but for the nutrients, rather than sugar content.)
A trowel in the hand is worth a thousand lost under a bush.
I did look at this a few years ago and read some interesting articles. Sugar (and other carbs.) molecules are too big to enter a plant via the roots, but apparently if you add fulvic acid this acts as a carrier molecule and can deliver carbs via the roots. I've not bothered trying. I did try fish emulsion a long time ago as a foliar feed - the smell was unbelievable! Molasses is useful as a foliar feed as it has many micro nutrients as Bob says above, however surely the leaves will end up sticky and attract all sorts of sugar seeking bugs..
I'll stick with seaweed extract, Tomorite and Miracle Grow
Billericay - Essex
Knowledge is knowing that a tomato is a fruit. Wisdom is not putting it in a fruit salad.
I have a book on growing Acers that says they use sugar solution to promote root growth in potted plants never tried it myself.
Google Percival, sugar and root. There is some published evidence for sugar improving root growth and increasing survival post transplant. I usually water anything bare root with a handful of sugar dissolved in a litre of water post planting. Just be careful to check the dose as too much can hinder growth. Not sure of benefit. Equally I haven’t noticed any harm.
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Sugar (and other carbs.) molecules are too big to enter a plant via the roots, but apparently if you add fulvic acid this acts as a carrier molecule and can deliver carbs via the roots. I've not bothered trying.
I did try fish emulsion a long time ago as a foliar feed - the smell was unbelievable!
Molasses is useful as a foliar feed as it has many micro nutrients as Bob says above, however surely the leaves will end up sticky and attract all sorts of sugar seeking bugs..
I'll stick with seaweed extract, Tomorite and Miracle Grow
Billericay - Essex
Knowledge is knowing that a tomato is a fruit.
Wisdom is not putting it in a fruit salad.
However, one of them has recently replaced that crop with medicinal cannabis
https://www.britishsugar.co.uk/media/news/2016-10-25-wissington-glasshouse-to-grow-plants-for-epilepsy-medicine
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
I live in west central Scotland - not where that photo is...
Billericay - Essex
Knowledge is knowing that a tomato is a fruit.
Wisdom is not putting it in a fruit salad.