Garden & Greenhouse


Using Molasses in Hydroponics

Posted June 12th, 2015 by Garden & Greenhouse in ,


Hydroponic gardeners wanting to reap the benefits of molasses during the flowering stage should use products designed for hydroponic systems, hand feed their plants, or foliar feed. Molasses is a great source of potassium during the flowering stage. However, using it in your reservoir can be difficult.

First of all, it will feed the bad bacterium that causes root rot and slime. Second, if not very diluted, it can clog pumps and drippers. As a result, if you’d like to get all of the benefits of using molasses without the headaches, I recommend using a product designed for hydroponic systems.

You can pour many of these products directly into your reservoir without worrying about slime or clogging your

system. Furthermore, these products are much more than just molasses. They contain beneficial trace elements and are more refined than molasses making the uptake of nutrients by your plants more efficient.

Another option is to use pure molasses diluted with water but instead of putting it directly in your reservoir, hand feed your plants with the mixture. Your plants will get all of the benefits of the molasses but you won’t have to worry about slime or a clogged system. The best choice is Blackstrap molasses (unsulphered).

Additionally, you can mix the molasses with water and put it in a spray bottle for foliar feeding. Combining molasses with other ingredients in a foliar feeding recipe is great because of its ability to chelate nutrients so they’re directly absorbed and used by the plant. Even though molasses contains highs levels of potassium, if you’re trying to make up for a deficiency of it, a better option is kelp.

Additionally, if you’re foliar feeding your plants, be sure to turn off your HID lights during the feeding. If you don’t, you run the risk of a water droplet acting as a magnifying glass resulting in your plants burning.

People have known for years that molasses and other sugars are great for plants. Just because you’re doing a hydroponic grow as opposed to soil, you don’t have to miss out. Either purchase products containing sugars that are made for hydroponic systems or consider hand watering or foliar feeding pure molasses.

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Want more information? Read these articles:

A Simple Build-It Yourself Hydroponic System

Hydroponic Grow Systems for Home

Hydroponic Systems Overview

Making Hydroponic Systems Efficient in Water and Reagent Use

Passive Hydroponics & Container Hydroponic Systems

Understanding the Different Types of Hydroponic Systems

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