Spring has pretty much hit the entire U.S. by this point, and that means it’s time to stop using your fireplace or wood stove as the days start getting warmer. You'll probably just clean up your ashes and toss them out with the rest of the garbage, but consider this before you do: you may be able to put those ashes to good use out in the garden. On the other hand, it's also important to keep in mind that not every garden needs wood ash added to it, and that adding it may even be detrimental to your soil.
Wood Ash Nutrients
Wood ash is an excellent fertilizer. It's full of potassium, calcium, phosphorus, and boron, and it doesn't add any unnecessary nitrogen to the soil. It’s often used similary to powdered lime sinces it raises the pH of your soil. You’ll need a more considerable amount of wood ash than you would powdered lime, of course, but if you already have some on hand from campfires, fireplaces, or a wood stove, you may as well make the most of it.
Test Your Soil First
Before you go tossing fireplace ashes around your garden, you’ll want to use a soil test to determine its pH. pH is measured on a scale that goes from zero to 14. Zero indicates that something is as acidic as it can get, seven is neutral, and anything above seven is alkaline. Many vegetable garden plants prefer a more neutral soil (i.e. soil wih a pH between 5.5 and seven). If your soil's pH is already above seven, you’ll want to avoid using wood ash.
Keep in mind that once you’ve applied the wood ash, you may want to test your soil again to see how it affects the pH. Another application could be needed if the pH hasn’t changed as much as you wanted. Still, multiple applications will always be easier to handle than putting too much into your soil first time and trying to reverse the effects.
Save Your Acidic Soil Loving Plants
Wood ash may be great for upping your soil’s pH, but there are still some plants out there that grow better when the ground has a lower pH. For that reason, you'll want to be careful about which plants you choose to expose to it. Plants like azaleas and blueberries, for instance, are much happier when your soil is more acidic.
Applying Wood Ash
To apply wood ash in your garden, simply sprinkle it where you need it and water it so that it works its way into the soil. Lawns can also benefit from a light application. As mentioned previously, it’s always a good idea to apply a little bit at first and add more as you go rather than going whole hog and ruining your soil's pH.
Tomato growers will be happy to know that you can also use wood ash to make a special potassium-rich tea that’s great for their plants. To do so, you’ll want to take about five pounds of the stuff and fashion a tea bag for it using a burlap sack or another material that’s permeable to water. Place this bag into a large garbage can, and then fill up the can as much as you can. Putting the bag in first will help keep the can from overflowing. Take the bag out after about four days, and use the tea on your tomatoes once a week. Pour a cup's worth around your plants after they’ve started to flower.
Wood Ash Dos and Don’ts
Always pay attention to the source of your ash. You only want to use ashes that come from real wood. You may have accumulated some ashes from charcoal or fake logs, but these won’t be beneficial to your garden.
You’ve probably heard that wood ashes are often used to make lye soap, and this process is only possible because the ash is a caustic material. This means that it can be dangerous to some of your plants. If you’ve recently planted seedlings or some other delicate plants, you’ll want to keep wood ash away from them to prevent burns.
You may think that you’re out of luck if you don’t have your own source of wood ash, like a fireplace or a wood burning stove. Instead of feeling discouraged, just ask around. You may find that a family member or friend may be willing to bag up their wood ash for you if they’re not already using it. Often, these people have to clean out their stoves anyways, so it's not like it'll be so much more inconvenient for them to save the ash for you. You’ll just want to be sure that it is pure wood ash you’re getting.
Finding new ways to use the items you already have laying around your house is always good. Wood ash may seem like a waste product now, but your garden can really benefit from the nutrient boost it has to offer.