Molasses for cannabis plants: what is it and why use it?

Molasses is a thick, dark syrup left over from making sugar, and growers add it to their watering to feed the beneficial microbes in the soil, which in turn help feed the plant. It's a great fit if you're growing naturally and organically. There are so many nutrients and supplements out there that molasses tends to fly under the radar, but it can really pay off in your grow.

Refining sugar leaves behind molasses, a dark, gooey syrup.  It's made by boiling down sugarcane or sugar beet juice into a thick syrup. Once the sugar crystals are pulled out, molasses is what's left. The trick is finding a molasses that actually works for your plants, since plenty of brands contain preservatives or chemicals you don't want.

Molasses is mainly used as a source of carbohydrates, though it's also rich in nutrients and does a good job of feeding the foundation of your grow, the soil. The easiest and most common way to use it is to dissolve it in your watering. Start with small doses to avoid nutrient burn and unnecessary stress.

There are two types of molasses: sulfured and unsulfured. Both contain a little sulfur, but sulfured molasses has added sulfur dioxide, which works as an antimicrobial and preservative. That means the very microbes you're trying to feed end up dying. Unsulfured molasses has no sulfur dioxide, so it feeds your plant without killing off the microbes a healthy growing medium needs. Your best bet is organic unsulfured molasses.

What is molasses and what does it do for plants?

Molasses is a liquid by-product of sugar production, made by processing sugarcane or sugar beets. It's a thick, dark, sticky liquid that contains a range of nutrients and beneficial organic compounds.

It's widely used in agriculture and gardening because of its nutritional properties and its ability to improve soil quality and support healthy plant growth. Here are some of its uses and benefits in the grow:

1. Source of nutrients: Molasses contains a mix of sugars, vitamins, minerals and organic compounds. These can be taken up by plants or released into the soil, supporting growth and development.

2. Boosts microbial activity: Molasses is food for the beneficial microorganisms in your soil. As they break it down, they release extra nutrients into the soil, improving its quality and making more nutrients available to your plants.

3. Improves soil structure: Molasses can help improve soil structure, boosting its water-holding capacity and aeration. That's good news for root growth and helps prevent problems like soil compaction.

4. Stimulates enzyme activity: Molasses is said to contain natural enzymes that may boost enzyme activity in the soil and in the plants, which could help with nutrient uptake and healthy metabolic processes.

Molasses or honey: which is better for plants?

Choosing between cane molasses and honey depends on what you're using it for. Here's how they compare:

1. Cane molasses: A by-product of sugar production made by processing sugarcane. It's rich in nutrients and organic compounds that are good for plants, and it's a common supplement in farming and gardening to improve plant growth and health. You can apply it to the soil or add it to your nutrient solution when watering. It's known for boosting microbial activity, improving soil structure and giving plants extra nutrients.

2. Honey: A natural product bees make from flower nectar. It has antimicrobial, antioxidant and nutritional properties, and it's widely used as a natural sweetener and in traditional medicine. In the grow, though, it's much less common than cane molasses. Honey can contain traces of pollen and other components that could throw off plant health and soil balance if you use a lot of it.

So if you're looking for a supplement for your plants, cane molasses is probably the better fit thanks to its nutrients and soil benefits. Honey, on the other hand, mainly belongs in the kitchen and the medicine cabinet. As always, follow the specific guidelines for your grow and check with gardening or agronomy pros for precise advice on using molasses or anything else.

What is “melaza”? Molasses in Argentina

In Argentina, “melaza” usually refers to the thick liquid by-product of refining cane sugar. It's a dark, sticky substance with a distinctive sweet flavor.

Argentines mostly use it as a natural sweetener in the kitchen, especially for desserts, sweets and drinks. It also goes into sauces, rubs and marinades for a unique flavor.

Beyond cooking, molasses is also used in farming and gardening as a plant supplement, to improve soil quality, stimulate microbial activity and give plants extra nutrients.

So in Argentina, molasses is known and used mainly as a natural sweetener in the kitchen and as a supplement in farming and gardening.

Keep reading about...