Organic fertilizers are a great way to improve soil fertility and promote healthy plant growth without the use of synthetic chemicals. Unlike synthetic fertilizers, organic fertilizers are made from natural ingredients such as animal and plant byproducts, making them an eco-friendly and sustainable choice for gardeners. Let’s start by understanding the NPK labels, explore the different types of organic fertilizers available, and how and when to apply them to your garden.
Understanding NPK
All fertilizers contain three primary nutrients, nitrogen (N), phosphorus (P), and potassium (K), which are essential for plant growth. These nutrients are referred to as NPK and are always listed on the fertilizer packaging in that order. For example, a fertilizer labeled 5-10-5 contains 5% nitrogen, 10% phosphorus, and 5% potassium. Understanding the NPK ratio is essential when choosing the right fertilizer for your plants, as different plants have different nutrient requirements.
Nitrogen: Initiates the growth process. Encouraging the development of fresh stems and leaves. Helps to promote green leaves and facilitates photosynthesis in plants.
Phosphorus: Development of roots, seeds, flowers, and fruits.
Potassium: Helps move nutrients around the plant, keeps the plant healthy, and helps them tolerate stress better.
I remember NPK by thinking “up, out, and all around.”
UP (Nitrogen promotes development)
OUT (Phosphorus promotes growth down to roots and out to stems)
ALL AROUND (potassium promotes overall health).
Don’t miss my post on Getting to Know Your Soil for more information on testing your soil for nutrient deficiencies!
Types of Organic Fertilizers
There are many different types of organic fertilizers available, each with its unique benefits. Some of the most popular types include:
Fish Emulsion: Made from fish waste, this fertilizer is high in nitrogen and is great for promoting healthy foliage growth.
Blood Meal: Made from dried animal blood. This fertilizer is high in nitrogen and is an excellent choice for promoting vigorous plant growth.
Bone Meal: Made from ground animal bones. This fertilizer is high in phosphorus, making it ideal for promoting root growth and flowering.
Compost: Made from decomposed organic matter, compost is rich in nutrients and is great for improving soil structure and fertility.
Seaweed Fertilizer: Made from seaweed, this fertilizer is rich in potassium and other micronutrients. It is an excellent choice for promoting overall plant health.
How and When to Apply
Organic fertilizers should be applied at the right time and in the correct amount to achieve the best results. Consider what type of nutrients your plants need at any given stage of growth. For example, I would apply a nitrogen-rich fertilizer when transplanting in the garden and a phosphorus-rich fertilizer as my plants are beginning to set fruits.
You can start applying organic fertilizers as early as the seedling stage. I suggest waiting until the seedling has at least one set of true leaves before fertilizing.
The next opportunity to add fertilizer is during the transplanting stage. When digging the hole for your plant, apply the amount of fertilizer given on the packaging in the hole and around the base of the plant.
Organic fertilizer should be applied throughout the growing season as well. The frequency and amount of fertilizer application will depend on the specific fertilizer and the plant’s needs.
For example, fast-acting fertilizers like fish emulsion should be applied every two weeks, while slow-release fertilizers like bone meal can be applied every three months. Some fertilizers like blood meal can burn plants if applied in large quantities, so it’s essential to follow the recommended application rates.
Organic fertilizers are an excellent choice for promoting healthy plant growth without the use of synthetic chemicals. By understanding the different types of organic fertilizers, and how to use them, you can create a thriving garden that produces abundant harvests while also being eco-friendly and sustainable!
