How to Use

Wood Ash

in the Garden

6 Benefits of Using Wood Ash in Garden Beds

Avoid applying ashes to the soil of acid-loving plants such as blueberries, hydrangeas, and potatoes.

1. Ash raises soil pH to  lower acidity.

Those nutrients include potassium, magnesium, phosphorus, sulfur, iron, manganese, zinc, and boron, among others.

2. It adds micronutrients  to the soil.

When worked into most soils, ashes add more air pockets, helping the soil to drain better.

3. It aerates heavy soil to  improve drainage.

Wood ash mixed in help soil crumble more readily, which means it is less compacted.

4. Wood ash makes soil  more friable.

However, you should never combine wood ash with nitrogen fertilizers, as that can produce ammonia gas.

5. It increases microbial nitrogen mineralization.

However, ashes cease being effective as a pest repellant once they become wet.

6. Sprinkled ash can repel slugs from plants.

Types of Wood Ash to Use  (or Avoid) in the Garden

Hardwood ashes, such as those from oaks and maples, contain more nutrients than those of softwood conifers such as pine and spruce.

Composting Wood Ash

Although you can include ashes in compost, they should never make up more than 5 percent of the pile.

Direct Application

Don’t allow wood ash to become wet before you apply it, or else many of the nutrients will leach out prematurely.

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