Does Molasses Improve Soil and Plants?

This is a hot topic in gardening these days and many gardeners are promoting the idea that you should add molasses to your compost pile, compost rea or even sprinkle it on your plants. In tea and soil it causes bacteria to grow and in plants it can prevent insects.

Molasses; should you eat it, or use it in the garden?

Molasses, what is it?

Molasses is a by-product produced during sugar production. Sugar cane or sugar beet is processed to extract the sugar. The material left after most of the sugar is removed is a dark sticky substance called molasses. It contains sugar, other carbohydrates, vitamins and a number of minerals such as calcium and iron. It may or may not contain sulfur.

Is Molasses Good for Bacteria?

Bacteria are opportunistic because their populations will increase and decrease as conditions change. Let’s assume you haven’t been gardening much so the conditions don’t change. In that case the number of bacteria remains constant. Things are moving at a normal pace and everyone is happy.

Now you throw a lot of molasses in the garden. Soon, the bacteria sensed more food and began to multiply. Bacteria in the lab can divide (ie, double in population) every 20 minutes. The population is exploding very fast. All those bacteria need food and they quickly eat the molasses you added. As the food source runs out there is starvation and most of the bacteria die.

What does molasses do?

Not much. It is true that all the dead bacteria go on to feed other bacteria, and help build the structure of the soil. The minerals in the molasses stay in the soil and the plants can use them, but your soil probably had enough calcium and iron before adding the molasses. The vitamins in molasses are not essential for plants.

Microbe growth bursts are short lived and add very little value to the garden and will not increase the number of microbes except for a very short time.

You might think that molasses is natural and therefore must be good for the garden. Organic fertilizers are good for the garden because they decompose slowly, feeding bacteria and plants for a long period of time. Adding sugar does not do this.

Should Molasses Be Added to the Compost Pile?

It doesn’t add much in terms of nutrients but people like to add it for bacterial growth. As noted above, it doesn’t really work as the sugar is used up very quickly. Sugar is also easily washed off the mound by the first rain.

Will Molasses keep insects away from plants?

It may be beneficial here if the molasses contains sulphur. Sulfur compounds are known to repel insects.

One problem with this solution is that sugar attracts insects that use it as a food source. Sugar can also lead to the growth of black mold on the leaves which can damage the plant and attract insects.

Even though sulfur repels insects, there are better options. Garlic or onion sprays can be very effective and are low in sugar.

Molasses in Compost Tea

Molasses is a common addition when making compost tea. Farmers believe that it causes high microbe numbers and they are right. The sugar in molasses is candy for bacteria and they eat it. I don’t think molasses is any better for this job than white sugar, but maybe?

However, there have been interesting studies showing that molasses increases bacteria growth, especially in compost tea. “Salmonella population increased from 1 to more than 1000 CFU ml^-1 in compost tea of ​​milk manure and 1% molasses, and from 1 to 350,000 CFU ml^-1 in chicken manure compost tea for 72 hours. E. coli the population increased from 1 to about 1000 CFU ml^-1 for both types of tea for 72 hours. Regrowth of the pathogen did not occur when molasses was eliminated or kept below 0.2%.

Do You Need to Feed Bacteria?

The main reason for adding molasses is to feed the bacteria, so it is important to ask, “is it important to feed the bacteria?” The answer is YES! However, there are many ways to do this. Adding compost, wood chips or other organic matter as mulch is the best option. This provides a slow, continuous feeding of bacteria.

You also don’t need to add purchased viruses.

Molasses is a product that we can use to feed people and animals. I’d rather eat gingerbread cookies than compost and wood chips. From an environmental point of view it makes sense to put edible organic matter in the garden and store food in the refrigerator.

There is no “magic” in molasses. It is just another source of organic matter that will decompose very quickly. All living things contain carbohydrates, sugars, minerals and vitamins, such as molasses. Don’t believe me …… look at the fact that molasses is made from plants; cane or beet sugar.