I wanted to learn more about how charcoal ashes affect my plants. I’ve heard old wives tales about using ash in the garden. But, I wanted to know if charcoal ash could truly benefit plants. You can find the results of my research below.
Charcoal ashes are good for plants because they can be used to improve pH levels of the soil, attract beneficial microorganisms, and add nutrients to the soil. You can also use it to get rid of certain harmful pests on your plants.
I’ve written a lot more details about charcoal ashes and their benefits in the post below. You will also find information on how to use the charcoal ash in your garden.
Why Charcoal Ashes Are Good For Plants
Turns out, the old tips and tricks you heard from your grandparents are true. Ash from charcoals can benefit your plants in several ways.
Meanwhile, potassium can strengthen plants by thickening the cell walls. Potassium also plays a big role in disease resistance and crop yield. This mineral is so important for plant growth that it’s one of the “Big Three” in commercial fertilizers.
Charcoal ash can do a lot to improve soil quality. However, there is one important caveat. You must use charcoal products that are free of additives and chemicals.
Using the Right Charcoal
You will find many different types of charcoal products on the market. Not all of them are going to work in your garden.
Briquettes are similar to charcoal. But, manufacturers produce it using compressed charcoal dust, wood shavings, or pulp. Any charcoal with a uniform shape is a briquette.
Ash from natural charcoal and briquettes are perfectly fine to use in your garden. The problem comes from treated charcoal products.
Many modern grilling products contain chemical additives. You might see products with lighter fluids and other ingredients that help with the cooking process.
Those are the types of charcoal ash you want to avoid. Even though the charcoal is burnt, you still run the risk of adding those chemicals to your garden.
If you want to use charcoal ash, stick to natural products that don’t contain any chemicals.
How to Use Charcoal Ashes
Charcoal ash is a versatile garden amendment that you can use to address a wide range of needs. Once you gather it from your grill, you can apply it to the soil, use it on your plants, and even toss it in your compost.
Here are some of the most common ways gardeners utilize charcoal ash.
Add to Compost Pile
Your compost heap is teeming with microorganisms. There are beneficial bacteria, fungi, and tiny insects. All of those organisms work together to break down carbon-containing organic waste to its simplest form. Once the decomposition process is complete, you’ll have nutrient-rich humus.
Adding charcoal ashes to the mix will only benefit the composting process. The ash will feed the organisms. Think of it as even more organic waste that you can turn into usable compost.
Correct Acidic Soil
If you’re dealing with acidic soil, charcoal ash is a good all-natural amendment. The ash’s trace amounts of potassium and lime make it more alkaline. Adding the alkaline ash will slowly raise the pH balance to neutral levels over time.
The potassium affects chemical reactions deep within the soil. During this process, the pH level rises. Because it happens deep below the surface, it’s at the prime spot for roots to take advantage of the change.
Raising the pH level of your soil takes time. In most cases, the process will not yield noticeable results until after a year or two. But, the change is worth it. High acidity levels affect the way plants absorb nutrients. Neutralizing it will create a garden that’s more conducive to plant growth.
Use for Pest Control
Use as Fertilizer
Those beneficial nutrients and minerals in charcoal ash can benefit your plants directly as a fertilizer. Just apply it like you would any other fertilizer. Sprinkle the ashes around the soil and work it in.
Do be careful about how much you use. As we mentioned earlier, ash will raise the pH level slowly over time. If you have acid-loving plants, you will encounter some growth issues.
Not only that, but you could overload your plant with potassium. This can change the way your plant uses nitrogen. Over time, the plant may experience nitrogen deficiency, which stunts growth and yellows foliage.
Protect Plants from Frost
Here’s a unique benefit you might not have thought of.
The mineral salts in charcoal ash can lower the freezing point of water in the soil. It’s the same scientific principles behind road salts. Dusting the plant leaves with ash and sprinkling some around the base of the plant can prevent frost damage.
It won’t keep them protected in very frigid temperatures. But if the climate is hovering around the freezing point, the charcoal ash can make a world of difference.
Is Wood Ash Good for Plants?
Wood ash is the powdery residue left over after burning a fire in a wood stove or campsite. It looks similar to charcoal ash and is often used interchangeably. But, wood ash is the byproduct of burned hydrocarbons.
It has a slightly different chemical composition and nutrient breakdown.
Either way, it’s also good for your garden. Many would argue that it’s better because you don’t have to worry about any chemical additives.
You can use wood ash the same ways you would charcoal ash. It’s particularly useful as a fertilizer. The nutrient breakdown is approximately 10 percent and 1 percent phosphorus.
Phosphorus is another important nutrient in commercial fertilizers. The nutrient is responsible for converting other nutrients into usable energy. It helps the plant store energy and even assists with photosynthesis.
Like charcoal ash, wood ash works well in the compost. It can also raise the pH level of the soil.
You don’t need a ton of ash to make a difference. Only a small amount can change your garden for the better.
Is Paper Ash Good for Plants?
Ash from the burnt paper is nearly identical to ash from wood. After all, the paper is merely wood pulp and other fibers. You can use it on your plants and achieve many of the same benefits.
However, you do need to be careful about the types of paper you use. Manufacturers use chemicals to improve strength and overall resilience. Bleach and chlorine treatments are common as well to create white paper.
There’s also the matter of ink. Large-scale printers might use inks with a range of chemicals and additives. Most inks from laser and inkjet printers are safe, as they contain natural oils. Newsprints are fine as well. But, you might want to err on the side of caution for paper products with a composition you’re not familiar with.