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USING CARBOHYDRATES – SUGARS relate to increased plant functions for Maximum Economic Yields.

Sugar Cane (HORTICULTURAL) or Black Strap Molasses is the best natural source – table sugar is more concentrated and also works; however, it lacks the Micronutrients intrinsic with molasses and it attracts insects.

ENVIRONMENTAL FACTORS that affect when and how much sugar to use:

a. How much excess nitrate (NO3) is in the soil and is in plant sap
(To find out order an Ask the Plant® petiole test)
b. Soil moisture conditions
c. Sunlight intensity
d. Temperature
e. Wind
f. Fruiting stage / load
g. Growth / vigor [shade of lower leaves]

The right supplemental amount of carbohydrates/sugar at the right time can improve fruiting and help produce normal plant growth with less attraction for disease and insects.

Natural Sugars are essential for healthy plants – fruit production – plant development and maturation.

Roots take nutrients from the soil and transport them up the stalk through the petiole (stem) to the leaves where the sunlight aids the production of photosynthates (sugars are not the ONLY product of photosynthesis) carbohydrates (C, H & O), principally glucose (C6H12O6) and many other sugars and photosynthates (hormones, enzymes, etc.) are formed.

Plant Sugars and other photosynthates are first translocated from leaves (Boron is essential for the translocation) to a fruiting site. If fruit is not available, the sugars, along with excess nitrates, spur the rapid vegetative growth of the plant at the expense of creating fruiting bodies (first sink) for the storage of the sugars. Once the proper balance of environmental factors (heat units, light intensity, soil moisture, nutrient balance, etc) are met, the fruiting buds form and then fruit formation gets the first crack at the sugar supply.

Any excess sugars are then translocated to the second sink, (growing terminals) to speed their growth. The left-over sugars then go to the third sink, (the roots) to aid their growth/activity. Here, the new root hairs take up nutrients, especially PHOSPHATE (PO4) to help continue the cycle of sugar and other photosynthates production for fruiting, growth of terminals and roots.


MOLASSES (Black Strap) is probably the best outside sugar source (contains many types of sugars, humics, high S [natural insecticide], K, Ca, Fe, trace elements, etc.) but also table sugar, corn syrup and several more complex sugars (polysaccharides) found in humus products. Molasses will not attract ants or other insects due to high Sulfur content.

Sugars can be added to the soil in irrigation water, drip and pivot being the most effective, or watering buckets.

In the soil it can supply energy to microbes feeding on carbon (humus) to stimulate the conversion of nitrates to the more efficient NH2 form of N to help synthesize protein directly by the plants without them having to utilize their natural sugar for energy for the conversion of NH4 — NH3 — NH2 the amine form.

  • The roots can directly absorb some of the sugars into the sap-stream to supplement the leaf supply to the fruit where it is most needed, and ALSO directly feed the roots and adjacent microbes for continued productive growth.
  • This ADDED sugar can also help initiate fruiting buds in a steady-slow fashion while maintaining normal growth (melons, peppers, cotton squares, peanuts, grapes, any multi-fruiting crop, etc.)
  • EXCESSIVE amounts of SUGARS applied foliar can shock the plant resulting in shortened growth internodes, increased leaf maturity and initiation of excess fruiting sites. This can be a short-term effect lasting only a few days. Pollination, soil moisture, nutrient balance and sufficiency as well as adequate light for photosynthetic production dictates how much of the induced fruit can mature.

ADDED SUGARS can be beneficial when Nitrates are excessively high in the soil and plants.

SOIL – Excess Nitrogen in the NO3 (Nitrate) form can be toxic; the N must be converted to the NH2 form for the development of protein N for the plant to properly assimilate. The conversion requires energy so the plant’s supply of natural carbohydrates (sugars) is utilized at the expense of better fruit development. Adding extra sugars to the soil supplies energy for the soil microbes to convert the nitrate so that the naturally produced sugars in the leaves do not have to be wasted supplying energy for the photosynthesis processes in the leaves, but then can directly support producing fruit.

Also, roots can utilize the extra sugars for their normal growth and plant functions, especially when the leaves are not producing adequate sugars for fruit, root and shoot growth, causing plant cut-out.

Sugars can be added to the soil in water and fertilizers.

PLANT – Sugars applied foliar to the plant are utilized much faster than soil applied, and there can be a shock effect if
overdosing occurs. Sugars can be directly assimilated into the photosynthesis process occurring in the leaf, speeding maturity and producing more natural sugars. This reaction occurs within hours of application and fades in a 3-7 day window. It supplements the naturally produced sugars and the excess is transported to the fruit producing areas to initiate fruiting buds or supply fruit development excess then goes to the growth terminals to sustain new growth and future fruiting sites: the remaining sugars go to the roots to sustain their new growth. (Young root hairs take up most of the phosphate which shows up in the sap with the petiole phosphate tests thereby predict plant cut-out).

A surfactant must be used with foliar-applied sugars to prevent burn spots on the leaves.

Foliar-applied sugars can reduce or eliminate frost damage as they increase the Brix of the plant sap, thereby lowering the freezing temperature of the sap. Must be applied before the frost.

  • Cloudy days and low sunlight intensity reduces natural sugar production causing less fruit set or sloughing young fruit, longer space between nodes and fewer fruiting buds.
  • Sugar is a source of energy for beneficial soil microbes. Microbes existing on soil organic matter can multiply faster when there is an abundant energy supply. Sugars supply energy for rapid microbial decomposition of raw organic matter and thereby release plant nutrients to roots, and conversion of nitrates to the organic form (amine nitrogen – NH2) that can be directly and efficiently assimilated into the plant processes.
  • Prevent leaf burn from repeated foliar sprays – Carbon (carbohydrates) buffers the caustic effect of many chemical nutrients and pesticides. Sugars, humus compounds, Urea and other carbon-containing compounds can protect leaf surfaces from damage and increase efficacy; must use proper amounts!

FOR SPECIFIC RECOMMENDATIONS OF SUGARS to prevent leaf burn or nutritional purposes we rely on the physiological stage of growth and the nutritional balance in the plant as determined by our ASK THE PLANT ® crop-logging plant analysis program. If nitrate is too high (promoting disease) the application rate of sugar goes up – If nitrate is low, the rate goes down. Phosphate (PO4) must be high for good root activity.

SUGARS have an array of functions on the SOIL FOOD WEB.
TOO MUCH OR TOO LITTLE can greatly affect
the plant development, fruiting and/or maturity!!

This is an oversimplification of very complex biological plant functions based on many published articles and on many trial and error TPS Lab®’s Ask the Plant® crop-logging petiole programs on hundreds of fields across thousands of acres.

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