Kiln-Dried Firewood

How to Use Wood Ash in the Garden

Do you enjoy working in the garden? If so, you should consider saving the leftover ash from your wood-burning fires. Whether you a build a fire in your fireplace, stove, chiminea or firepit, it will create ash as a byproduct. While you can always dispose of wood ash, it's unique properties make it particularly useful in the garden.

Why Wood Ash Is Good for Plants

Wood ash is an excellent source of potassium -- a nutrient that all plants need to survive. In fact, potassium is considered the second-most important nutrient for plants, surpassed only by nitrogen. Plants use potassium for metabolic purposes, such as converting starches into sugars. Potassium also helps to balance the water level in plants. If a plant doesn't get enough of this essential nutrient, it will be susceptible to drought.

Furthermore, wood ash contains nitrogen and phosphorus, which also play a key role in the health and development of plants. Nitrogen acts as a catalyst for photosynthesis by allowing plants to produce chlorophyll, whereas phosphorus helps to regulate protein synthesis, as well as other cellular processes, in plants.

Countless store-bought fertilizers contain potassium, nitrogen and phosphorus, but an equally effective source of these essential plant nutrients is wood ash. Wood ash is nothing more than burned plant matter (trees). As a result, it contains all the essential nutrients plants need. When you use wood ash in your garden, you'll supply your plants with nutrients like potassium, nitrogen and phosphorus.

Wait Until the Ash Is Cool

If you're going to use wood ash in your garden, wait until it's completely cool. Handling hot ash is never a good idea, as it could result in bodily injury. At the same time, exposing plants to burning-hot ash may harm or even kill them. To protect yourself, as well as your plants, from injury, wait until the ash has cooled. Depending on factors such as the size of the fire and humidity level, it may take up to 48 hours for ash to fully cool. Only after the ash is completely cool, though, should you use it in your garden.

Use Wood Ash, Not Charcoal Ash

It's important to note that you should only use wood ash in your garden and not charcoal ash. What's wrong with using charcoal ash? Like wood ash, charcoal ash consists of burned plant matter. The difference is that charcoal often contains additives that are harmful to plants. For example, it's not uncommon for charcoal to contain sulfur oxide, which acts as a fire accelerate so that it's easier to light. If you use charcoal ash in your garden, you'll expose your plants to this harmful chemical. In addition to sulfur oxide, charcoal may contain synthetic additives like borax or paraffin that are also harmful to plants. By using wood ash, you can rest assured knowing that your plants won't be exposed to these harmful chemicals.

Keep in mind, not all wood ash is the same. Wood ash from hardwoods like oak and hickory is typically better for plants than wood ash from softwoods like pine and redwood. Softwoods contain more resins and less nutrients than hardwoods. So, if you're going to use wood ash in your garden, make sure it's hardwood ash and not softwood ash.

Compost Bin

Add it to a Compost Bin

Wood ash is an excellent ingredient for a compost bin. If you have a compost bin in your garden, consider tossing your leftover wood ash into it. The secret to creating nutrient-rich, beneficial compost is to add ingredients rich in potassium, nitrogen and phosphorus. As previously mentioned, wood ash contains all three of these essential plant nutrients. Just toss the wood ash into your compost bin, shuffle it around with a large shovel or pitchfork, and wait for the rest of the compost to decompose. You can then add your homemade compost to plants and trees to boost their health.

Besides wood ash, some of the other ingredients you can add to a compost bin include the following:

  • Coffee grounds
  • Fruit and vegetable scraps
  • Eggshells
  • Grass clippings
  • Leaves
  • Twigs
  • Tea leaves
  • Sawdust (assuming it's from non-pressure-treated wood)
  • Newspaper
  • Weeds

Sprinkle It in Flowerbeds

Even if you don't have a compost bin or compost pile, you can still use wood ash by sprinkling it in flowerbeds. Regardless of what type of plants you are growing, they can benefit from the nutrients found in wood ash. Just fill a small cup or container with wood ash and sprinkle a small layer over the soil in your flowerbeds. As the wood ash settles into the soil, it will leach nutrients like potassium, nitrogen and calcium, which are then absorbed by the roots of the surrounding plants.

You don't have to sprinkle a lot of wood ash into your flowerbeds. On the contrary, just a small and thin layer will suffice. Just remember to use wood ash from hardwoods for maximum benefit. Softwood ash contains some nutrients, but it pales in comparison to the nutrient-rich makeup of high-quality hardwood ash.


Create a Pest Barrier Around Trees and Plants

You can also use wood ash to create a pest barrier around trees and plants. Pests such as slugs and snails will avoid walking slithering their way over wood ash. As a result, wood ash offers a safe, all-natural way to protect trees and plants from these and other common pests. If you want to protect a specific tree from pests, for instance, sprinkler wood ash in a circle around the tree. As long as the wood ash remains present, pests such as slugs and snails won't be able to reach the tree.

Of course, you'll need to reapply the wood ash if it rains. Rainwater will wash away the wood ash, leaving the tree or plant susceptible to pests. Therefore, it's a good idea to store some of your excess wood ash so that you can reapply as needed.

Balance pH Level

What's the pH level of the soil in your garden? Plants require a specific pH range to grow. If the soil's pH level is too low, your plants may struggle to grow. The good news is that you can use wood ash to balance the pH level of your soil. With its high calcium content, wood ash will raise the pH level of your soil. With that said, you'll first need to test the pH level of your soil to determine exactly how acidic or alkaline it is. Assuming the pH level is lower than that required by your plants, you can proceed to add a small amount of wood ash, followed by retesting the pH level several days later. If it's still low, add a little more wood ash until you've achieved the desired pH level.

These are just a few ways to use wood ash in your garden. When working in your garden, you'll probably discover other practical uses for wood ash.

Stock up on premium kiln dried firewood by visiting our online store today. We offer a variety of kiln dried firewood, including oak, hickory and more, that will help you build clean fires in your fireplace. And rather than disposing of the ashes, you can save them to use in your garden.

About The Author

Leroy Hite

Leroy Hite is the founder and CEO of Cutting Edge Firewood, an ultra-premium firewood and cooking wood company located in Atlanta, Georgia. Leroy's mission is to give people the experience of the perfect fire because some of life’s best memories are made in the warmth of a fire’s glow. He founded Cutting Edge Firewood in 2013 with a goal to provide unmatched quality wood and unparalleled customer service nationwide. The company offers premium kiln-dried firewood, cooking wood, and pizza wood in a wide variety of species and cuts to customers around the country.