How to Use Ash from Your Wood Burner in the Garden

If you have a wood-burning stove and burn natural, untreated wood, you’re creating more than just warmth, you’re also making a fantastic natural soil amendment! Instead of throwing away the ash, why not put it to work in your garden? Wood ash is rich in potassium, calcium, and other trace minerals, making it a wonderful addition to your soil when used correctly.

Let’s dive into the benefits of wood ash for gardening, which plants love it, when to use it (and when not to), and how you can start incorporating it into your garden today!

Why Use Wood Ash in the Garden?
Wood ash is packed with essential nutrients that can boost plant growth and improve soil health. Here’s why it’s worth saving those ashes:

• Rich in Potassium (K): This helps flowering and fruiting plants thrive, encouraging stronger blooms and bigger harvests.
• Contains Calcium: Just like lime, wood ash can help reduce soil acidity and prevent issues like blossom end rot in tomatoes.
• Natural Pest Deterrent: Sprinkling ash around plants can deter slugs and snails, as it dehydrates them.
• Encourages Earthworms: A light dusting of wood ash can improve soil structure and microbial life, making it more inviting for worms.

Which Plants Love Wood Ash?
Not all plants enjoy wood ash, but the ones that do will thank you with stronger growth and healthier yields!

• Brassicas (Cabbage, Broccoli, Cauliflower, Brussels Sprouts, Kale) – Wood ash raises soil pH, helping to prevent clubroot. 
• Tomatoes & Peppers – The potassium helps boost flowering and fruit production.
• Beans & Peas – Enjoy the extra minerals without needing too much nitrogen.
• Garlic & Onions – Helps with bulb formation and strengthens plants.
• Fruit Trees & Berries – Apple trees, raspberries, and currants benefit from potassium and calcium.

When Not to Use Wood Ash
While wood ash has plenty of benefits, some plants and situations call for caution:

• Acid-Loving Plants (Blueberries, Rhododendrons, Camellias, Cranberries) – Wood ash raises pH, which they won’t like.
• Potatoes (if used too much) – Too much ash can increase the risk of potato scab.
• Carrots & Parsnips (in excess) – A sudden pH change can cause forking roots.
• If Your Soil is Already Alkaline – Adding wood ash to high-pH soil can make it too alkaline, which reduces nutrient availability. (Test your soil first if you’re unsure!)

How to Use Wood Ash in the Garden

• Sprinkle lightly on soil – Use about a handful per square metre and mix it in gently.
• Add to compost – Helps neutralise acidity and balance your compost pile.
• Use around plants as a slug deterrent – A fine ring of dry ash can keep slugs at bay (but reapply after rain).
• Apply in winter or early spring – This gives time for nutrients to settle before planting.
• Water in after applying – Prevents ash from blowing away and helps it integrate into the soil.

Sustainability in Action: Give It a Try!
If you have a wood-burning stove, using wood ash in your garden is a fantastic, free, and eco-friendly way to improve your soil and help your plants thrive. Just remember to use it wisely, test your soil if needed, and avoid using it on acid-loving plants.

Have you used wood ash in your garden before? Let me know in the comments or tag me on Instagram @thekitchengreenhouse to share your experiences! 🌱

Happy growing!