When plants receive too much fertilizer, the excess nutrients can build up in the soil and cause damage, a condition known as over-fertilization or fertilizer burn. The primary method to address this issue is to leach the excess nutrients from the soil by using watering to slowly flush out the pot.
This process involves saturating the soil with plain water to dissolve the accumulated salts from the fertilizer and wash them away from the plant's roots.
Steps to Remove Excess Fertilizer (Leaching)
Dealing with over-fertilization requires prompt action to minimize stress and damage to the plant. Here are the key steps:
- Assess the Damage: Examine the plant for signs of fertilizer burn, such as browning or crisping leaf edges, wilting, stunted growth, or a white crust on the soil surface.
- Prepare for Leaching: Move the plant to a location where water can drain freely, such as a sink, bathtub, or outdoors. For potted plants, ensure the pot has drainage holes.
- Leach the Soil Thoroughly: According to the reference, the best way to solve the problem of over-fertilization is to leach excess nutrients from the soil by using watering to slowly flush out the pot. Use a large volume of plain water (without fertilizer) – ideally, at least four times the volume of the pot. Slowly pour the water through the soil, allowing it to drain completely before adding more. This helps dissolve and wash away the excess salts.
- Repeat (If Necessary): For severe cases, you may need to repeat the leaching process after an hour or so to ensure maximum removal of salts.
- Remove Damaged Parts: The reference advises to remove any severely damaged leaves. These leaves will not recover and can drain energy from the plant. Also, if there is a visible crust of fertilizer on the soil surface, you can be careful not to remove more than a ¼ inch of soil to prevent stressing the plant. Gently scrape away this top layer.
- Allow Drainage: Let the pot drain thoroughly after leaching. Do not let the plant sit in standing water.
- Provide Recovery Time: Place the plant in a suitable location (usually out of direct sun) and avoid fertilizing it for at least a month or two to allow it time to recover. Monitor the plant for new growth.
Practical Tips for Leaching
Effective leaching is crucial for plant recovery.
- Use Sufficient Water: Don't be afraid to use a large amount of water. The goal is to flood the soil to wash out salts.
- Slow Watering: Pouring water slowly ensures that the entire soil ball is saturated and water doesn't just channel down the sides.
- Check Drainage: Make sure the pot drains well. Poor drainage can exacerbate root issues.
Signs of Over-Fertilization & Actions
| Sign | Action Needed |
|---|---|
| Browning/crisping leaf edges | Leaching soil, remove damaged leaves |
| White crust on soil | Gently scrape off top layer (max ¼ inch), then leach |
| Stunted growth after fertilizing | Leaching soil, monitor plant |
| Wilting despite watering | Leaching soil, check roots for damage |
By following these steps, particularly the crucial leaching process highlighted in the reference, you can effectively remove excess fertilizer from the soil and give your plant the best chance at recovery.
