Wood ash is a natural, organic fertilizer that adds essential nutrients to soil while improving its structure. It’s especially useful for acidic soils as it helps raise pH levels.
Nutrients in Wood Ash
Wood ash contains several important minerals:
✅ Calcium Carbonate (Lime) – Helps neutralize acidic soil
✅ Potassium (K) – Strengthens plant resistance & improves fruiting
✅ Phosphorus (P) – Supports root development & flowering
✅ Magnesium (Mg) – Essential for chlorophyll production
✅ Trace Minerals – Includes iron, zinc, and manganese
Benefits of Using Wood Ash in the Garden
✔️ Neutralizes Acidic Soil – Acts like lime to raise soil pH
✔️ Provides Potassium & Phosphorus – Boosts plant health
✔️ Improves Soil Structure – Enhances soil aeration & drainage
✔️ Natural Pest Repellent – Deters slugs, snails, and soft-bodied insects
How to Use Wood Ash as Fertilizer
1️⃣ Soil Amendment (Increase pH & Add Nutrients)
Sprinkle lightly (½–1 cup per square meter) on garden beds.
Mix into the soil before planting.
Avoid using on alkaline soils (pH above 7) or around acid-loving plants.
2️⃣ Compost Booster
Add in small amounts to compost piles to increase mineral content.
Do not mix with nitrogen-rich materials (manure, green leaves) as it can cause ammonia loss.
3️⃣ Pest Repellent (Against Slugs & Snails)
Sprinkle a thin layer around plants to create a barrier against pests.
Reapply after rain, as water washes it away.
4️⃣ Liquid Fertilizer (Wood Ash Tea)
Mix 1 cup of wood ash with 5 liters of water.
Let it sit for 24 hours, then use it to water plants for a potassium boost.
Important Precautions
Do not use on acid-loving plants like blueberries, azaleas, and rhododendrons.
Avoid mixing with fertilizers that contain ammonium (like urea) to prevent nitrogen loss.
Use in moderation – Excess wood ash can alkalize the soil too much.
Best Plants for Wood Ash Fertilizer
✅ Tomatoes
✅ Peppers
✅ Roses
✅ Garlic & Onions
✅ Fruit Trees