Solubility – The Key to Plant Nutrition

PHLOEM, XYLEM AND EVAPOTRANSPIRATION – THE PLANT’S NUTRIENT TRANSPORT SYSTEM

All higher plants (including grasses, vegetables, and trees) have a vascular system which is analogous to an animal’s circulatory system. The plant vascular system consists of two primary types of tissues that are typically bundled together: xylem and phloem. Phloemtubules carry sugar, other organic compounds and minerals around the plant. Typically, sugar is transported down to plant roots as an energy source for root growth. Xylemtubules transport water and are responsible for keeping the plant hydrated. Water is drawn from the ground into the roots where it is pulled upward through the stem, all the way to the leaf or blade, where it eventually exists through stomata. (Stomata are tiny pores on leaf blades that open and close to control the rates of water loss and gas exchange). The entire process of water being drawn through the plant is called evapotranspiration. Because water has cohesive and adhesive properties (meaning water likes to “stick” to surfaces, as well as itself), when water evaporates out through a stomate, another water molecule gets pulled into the stomate to take its place. Essentially, xylem tubes facilitate an unbroken chain of water molecules that are constantly being pulled upward through the plant. This is critical because this is how nutrients from the ground are transported to all parts of the plant; they are dissolved in the water located inside xylem tissues. In other words, nutrients that are not soluble cannot be used by plants.

STATE OF SOLUBILITY AT DELIVERY – WHICH FERTILIZERS PERFORM BETTER: GRANULAR OR LIQUID PRODUCTS?

Much study has gone in to determining if granular or liquid fertilizers are more effective at delivering nutrients to the plant. As it turns out, as long as the nutrient source, environmental conditions and application rate are the same, both are equally effective. When nutrients are already dissolved in water, they are immediately absorbed into the ground. In the case of granular fertilizers, if the ground is sufficiently saturated due to heavy irrigation or adequate rainfall, the same nutrients will readily dissolve at disperse into the soil in the same manner as if they were delivered in liquid form. In the case of turf, two benefits that come from liquid fertilizer applications are the immediate penetration of nutrients into the soil, as well as a more even distribution of nutrients across the soil surface. But remember, given adequate ground saturation, nutrients delivered from granules will disperse just as easily given enough time. 

Whether mixing nutrients, soil amendments, or pesticides, ALWAYS read and understand the label AND perform a small-scale jar test with new combinations of ingredients before large scale tank mixing. If you have any questions or concerns, contact the product’s manufacturer before proceeding.

Solubility & Compatibility – master these two concepts and your fertilizer programs is sure to give you fantastic results whether your growing turf, ornamentals, trees, or vegetables!

For professional fertilizers, humic and AMP-XC™ enriched products available, please visit TurfCare’s online Product Catalog.

For green industry professionals or others interested in ordering Turfcare products, please contact our Customer Service to find a distributor near you.