Monday, March 24, 2014

Don't kiss your ashes goodbye!

The last hurrah of winter has almost come. You've burned wood. You have ashes. Now what? Don't Throw Them Away!
Wood ash, also known as potash, is an excellent, organic amendment for soil. It is full of micronutrients (calcium, zinc, and magnesium, to name a few) and is an effective and organic way to raise (make more alkaline) your soil's pH. And it's free! This makes wood ash an excellent resource, providing your need soil needs a bit of alkalinity.

Wood ash is a form of potassium. Reflecting on that lovely Table of Elements chart from Chemistry 101, you may recall that the chemical symbol for potassium is "K." This is the K in the NPK ratio on those fertilizer bags. Potassium is a much-needed nutrient for plants, enabling them to use water more efficiently, resist drought and disease, and simply strengthens them overall.

There are only a few caveats to using leftover wood ash in your garden. Wood ash as a soil amendment specifically means ashes from wood you have burned, not ashes from your charcoal grill. Think 'tree only,' and this means as it fell; no treated wood. Also, if your soil is already quite alkaline, forego the wood ash. (What?! Too alkaline? How do I know this?! Now might be the time to become friendly with that soil testing kit you've been threatening to purchase.) And while potatoes may appreciate a good dose of potassium, too much wood ash can cause scab. So use with caution around potatoes. 

Understanding pH
In the world of pH, 7.0 is neutral. Soil that registers lower than 7.0 is considered acidic. If the level is higher, it is considered alkaline, or sweet. Most plants appreciate a nearly neutral soil pH of about 6.5-7.0, but some thrive in an environment that is more acidic. It is critical to know the pH requirements of your plants and how your soil registers. If you apply wood ash willy nilly to your garden, it could mean impending doom for some plants. Raising the pH of your soil is great for tomatoes, for example, but it would be disastrous for acid-loving blueberries or azaleas.

How to apply
Avoid windy days when working with wood ash and be sure to use protective gear. Gloves, mask, and eye wear are all de rigueur. The easiest way to incorporate wood ash into your soil is to compost it. Be careful, however, not to mix in too much at one time or you will skew the pH and scare off those beneficial worms at work. Add a thin layer alternated between those leaves or kitchen scraps. You can also lightly sprinkle wood ash directly on the soil, which will also function as a slug deterrent. If you miss the soil and it finds its way to the leaves of your plants, wash off the leaves to prevent burning. If using for slugs, reapply after a rain.

It's the Bee's Knees
Beekeepers should especially take note – wood ash is excellent for that clover yard you have been coveting. Clover thrives in a pH of 6.5 to 7. If your soil leans toward acids (very common in these parts), it will thank you for broadcasting a light layer of wood ash and repay you with oodles of happy little clover plants. 

If your soil could benefit from a little pH adjustment, now might be a great time to address that issue. So be sure to save those ashes and do some down-to-earth recycling. And, ya can't beat the price!

1 comment:

Thanks for the comment! If it requires a response, I will get back to you as soon as I can. Thanks for reading my blog!