Molasses, a highly viscous by-product of sugar refinement, is a great supplement for improving your garden. Molasses is rich in both micro- and macro- nutrients, is a great source of carbohydrates for soil microbes, and subsequently boosts the structure and moisture retention of the medium, and encourages growth of beneficial organisms. Molasses also aids in the reduction of salt build up, which is a common cause of nutritional problems, and is a useful insect repellent. While microbes thrive on the sugars in molasses, ingesting molasses for an insect is imminent death (Excluding Sugar Ants and Bees).
Not all molasses is the same, however. Some are made to a lesser quality, and may contain preservatives and other chemical additives that are unwanted in the garden. There are two types of molasses: Sulphured and Unsulphured. While both of types do contain sulphur, the major distinction is that sulphured molasses contains sulphur dioxide, which acts as a preservative and anti-microbial substance. This means that sulphured molasses will actually kill the microbes you are trying to feed. So make sure that you only use unsulphured, organic molasses. There are three grades of molasses, from lighter to darker: mild (a.k.a Barbados), dark, and blackstrap. Blackstrap molasses is preferred for its higher mineral and vitamin content. Blackstrap is high in calcium, magnesium, iron, potassium, and micronutrients.
There are multiple ways to incorporate molasses into your garden. It is often used as part of a regular feeding schedule, in foliar sprays, composts and compost teas, and during soil preparation. Dosage is determined by personal experience: Each garden and plant is different, some may prefer a larger or smaller dosage depending on their environment, health, size, and age/stage. To be safe, using a starting point of 1 tablespoon (15 ml) of molasses per gallon (3.8 liter) of water for feedings is a good rule of thumb. It is recommended to increase molasses dosage as the flower stage progresses, as the plant will require more potassium. Using small dosages will help prevent any unnecessary risks such as stress or nutrient burn, and allow you to correctly determine a favorable future dosage. For use as an insecticidal foliar spray, 1 teaspoon (5ml) per gallon is recommended.*Mix molasses in lukewarm water before adding to reservoir, bucket, or spray bottle to allow it to fully dissolve.
There’s also Dry molasses, which isn’t actually dried molasses – It’s a grain residue carrier that has been drenched in liquid molasses. Dry molasses contains more sugar than liquid molasses, but can’t be mixed into water. It’s recommended to apply 1 lbs. of dried molasses per 50 sq. ft.
The benefits of molasses will be most noticed during the flowering period. Molasses can also be added/combined with other organic liquid fertilizers and sprays, such as compost teas, kelp, alfalfa, and milk. It is also safe to use molasses at the same time as nutrient feeds, however it may subsequently cause fluctuation in soil pH, so it is important to remember to check run-off pH. Using molasses on just-water days or during a flush is also beneficial.
For the outdoor grower, it’s important to note that molasses is commonly used by hunters to attract game, so be aware of your local wildlife, or they may end up eating your crop!
Here is some info hope this helps
IE; Original post from Oaksterdam Uni.
Copied/pasted/posted by Majiktoker