Feeding and Fertilizing Plants
Plants need nutrients for healthy growth, but fertilizer should be used thoughtfully. More fertilizer is not automatically better.
Essential Nutrients
Nitrogen, phosphorus, and potassium are required in relatively large amounts. Plants also need several secondary and micronutrients.
Each nutrient contributes to different biological functions.
Reading Fertilizer Labels
Fertilizer labels show the nutrient analysis and provide application instructions. Follow the recommended rate rather than guessing.
Types of Fertilizer
Granular fertilizers are applied to soil and may provide nutrients over different periods. Liquid fertilizers can act quickly and are often useful when precise application is desired.
Slow-release products supply nutrients gradually.
Organic and Synthetic Fertilizers
Organic fertilizers are derived from biological or naturally occurring materials. Synthetic fertilizers are manufactured to provide specific nutrients.
Either type can be useful when applied correctly.
Recognizing Nutrient Problems
Yellowing, poor growth, abnormal coloration, and other symptoms can have many causes. Do not automatically assume a symptom indicates fertilizer deficiency.
Watering problems, root damage, pests, diseases, and environmental stress can produce similar symptoms.
Avoid Overfertilizing
Excess fertilizer can damage roots, encourage excessive vegetative growth, and contribute to environmental pollution.
Soil testing can help determine whether additional nutrients are needed.
The Major Nutrients
Nitrogen is strongly associated with vegetative growth. Phosphorus participates in energy transfer and reproductive processes, while potassium plays roles in water regulation and numerous plant functions.
Plants also require calcium, magnesium, sulfur, iron, and other micronutrients.
Fertilizer Does Not Fix Every Problem
Before fertilizing a struggling plant, ask:
- Is it receiving enough light?
- Is the soil too wet or too dry?
- Are roots damaged?
- Are pests present?
- Are there signs of disease?
- Is the plant naturally entering a different growth stage?
Adding fertilizer to a plant suffering from root damage can make the situation worse.
Reading a Fertilizer Analysis
A fertilizer label may show three major nutrient numbers representing nitrogen, phosphate, and potash in the conventional analysis system.
Always follow the label's application instructions.
Slow-Release Versus Fast-Release
Slow-release fertilizers provide nutrients over an extended period, while readily soluble fertilizers can become available more quickly.
Neither is automatically appropriate for every situation.
Fertilizing Containers
Container plants have limited nutrient reserves. Some may require periodic feeding, depending on the growing medium and fertilizer already incorporated into it.
Record Applications
Keep a simple fertilizer record with product, amount, date, and area treated. This prevents accidental repeated applications and helps evaluate results.
Conclusion
Feeding and Fertilizing Plants is a skill that becomes easier with practice. Use the principles in this guide as a foundation, observe how they apply in your own garden, and adjust your approach as you gain experience.