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Whenever I clean out my fridge or pantry, I find myself wondering if random expired food can be composted. This is exactly how I found myself wondering if my 5 years expired blackstrap molasses could be useful in my garden. I found myself Googling, “can you compost molasses?”, and I was so excited to find that organic molasses in compost promotes the growth of beneficial microorganisms.
So I did what any normal science minded gardener would do and dove into the online literature. After reading all the benefits of unsulfured blackstrap molasses in a garden, I knew that my expired molasses would feel right at home in my compost bin. Here’s what I learned about using molasses as a natural fertilizer and how to prep it for your compost bin.
Benefits of molasses in compost and garden
Liquid molasses is such a valuable addition to your compost bin and garden because molasses contains trace minerals and vitamins. Blackstrap molasses contains calcium, magnesium, potassium, and iron. It makes me wonder why I’m not consuming molasses more myself! I’m seriously considering adding a teaspoon to my coffee each morning. Someone tell me if this is a thing!
Molasses also contains complex sugars, which makes sense because molasses is actually the by-product of the sugar refinement process. When sugar cane and sugar beets is refined, molasses is left behind. Brown sugar is actually made from molasses and white sugar. Don’t you just love fun little science/ food/ gardening facts? The sugars/ carbohydrates in molasses aren’t able to be processed by plants. Think back to biology and photosynthesis- plants make carbohydrates, so it make sense that they can’t actually process them in the uptake of vitamins and minerals.
While the sugar isn’t directly beneficial to the plants, it is indirectly beneficial by providing microbes (beneficial bacteria) in the soil with food and energy. These beneficial microbes break down nutrients and release them into the root zone of your plants’ roots.
Just think, the molasses that you could have tossed in the garbage can do so much good in your garden. Makes you wonder what else you are sending to the landfill that could benefit our soil, right?
What is the difference between sulfured and unsulfured molasses? And does it matter to my organic garden?
When molasses is made from derived sugar, it can be made in one of two ways: with sulfur dioxide or without. Sulfured molasses is made from immature, green sugar cane and includes sulfur dioxide. The sulfur dioxide acts as a preservative and gives sulfured molasses a chemical note.
Unsulfured molasses is made from mature sugar care and does not require sulfur dioxide. Unsulfured molasses is considered to be more pure and is actually more common. Unsulfured molasses is what we recommend for using in your compost or garden. The mature sugar, and the lack of sulfur dioxide makes it a much easier for microbial activity to occur.
Why blackstrap molasses? Can I use any type of molasses in my garden?
Now that you know the difference between sulfured and unsulfured molasses, it’s time to learn the other 3 types of molasses: light, dark, and bootstrap.
You can use any type of molasses in your compost and garden. Bootstrap has the highest levels of minerals so I definitely recommend that over the other two. However, if you find yourself with any type of old molasses in your pantry, by all means use it in your compost!
How do I compost my molasses?
There really is no wrong way to add molasses to your compost pile. You can add it directly or dilute it with water. I find that the easiest way to do this is to add water to the bottle of molasses, shake vigorously, and then add directly to your compost. You can even use dry molasses directly in your compost bin, if you happen to have some of that on hand.
Can I add molasses to my worm bin?
Yes! Worms love the sweet taste of molasses. The sugars feeds the microorganisms in the worm bin, allowing the worms to take up more nutrients from the soil.
Just make sure to dilute your molasses with water first and spread it out throughout your worm bin. You might even want to stir it around in the bin to distribute the molasses.
How to use molasses as an organic fertilizer
You can take a couple extra steps and use molasses directly in your garden soil. A molasses mixture with water can rival other organic liquid fertilizers on the market. It most certainly can outperform synthetic fertilizers and promote healthy soil.
Add 2 tbsp liquid molasses to 1 gallon of water. That’s it!
Feed the water mixture directly to your soil in your organic garden and the soil microorganisms will have a hay-day with this quick source of energy!
This is an easy thing to add to your organic gardening practices. Adding these organic wastes to your garden is low cost way to promote healthy microbes in your soil.
How often should I add molasses to my garden or compost?
As much as I love the idea of adding molasses to my garden, I don’t think I’ll go out and buy it solely for the purpose of adding it to my garden or compost pile. It’s a great addition if you find yourself with some molasses at the end of a jar and you don’t know what to do with it.
That being said, your garden or compost pile really only needs a molasses fertilizer treatment about once a year for healthy plants.
How to use molasses as a natural insecticide
Did you know that you can also use molasses to deter pests like aphids? I was super excited to find this smart tip that other organic gardeners swear by for my garden!
Make the same mixture that you would use for your soil (2 tbsp of liquid molasses to 1 gallon of water) and use as a foliar spray directly on your plant leaves. This works because the high amount of simple sugars isn’t great for bugs. They will use the molasses as a food source and get dehydrated.
Like this post?
You’ll probably like these other garden hacks and tips that I’ve shared:
- How to use fermented banana water in your garden
- How to troubleshoot awl snails
- How to use your worm castings