Soil Amendment

Blood Meal: A Versatile Organic Fertilizer and Pest Deterrent

What Is Blood Meal?

Blood meal is a natural fertilizer made from the dried blood of slaughtered animals, primarily cows. It is a rich source of nitrogen, essential for plant growth and development. Unlike bone meal, which provides calcium and phosphorus, blood meal primarily supplies plants with nitrogen.

Benefits of Blood Meal

High Nitrogen Content: Blood meal contains a high percentage of nitrogen, making it an effective fertilizer for plants suffering from nitrogen deficiency.
Pest Deterrent: The distinct odor of blood meal repels certain pests, such as deer, rabbits, and moles.
Organic and Environmentally Friendly: Blood meal is an organic fertilizer that does not contain harmful chemicals.
Soil Acidification: Blood meal can acidify soil, which benefits acid-loving plants like azaleas and blueberries.
Slow-Release Fertilizer: Blood meal releases nutrients slowly over a period of 1 to 4 months, providing sustained nourishment for plants.

Disadvantages of Blood Meal

Excessive Nitrogen: Overuse of blood meal can lead to excessive nitrogen levels in soil, which can inhibit flowering and even burn or kill plants.
Cost for Large Gardens: Blood meal can be expensive to purchase in large quantities for large gardens.
Attracts Carnivores: The odor of blood meal can attract carnivores, such as dogs, to your garden.
Not Suitable for All Plants: Some plants, such as those that prefer alkaline soil, may not tolerate the acidic conditions created by blood meal.

When to Use Blood Meal

Apply blood meal in spring when you first observe plant growth.
Reapply every 2 to 3 months throughout the growing season.
Use 1 to 2 pounds per 100 square feet.
A 2-pound application is considered a heavy feeding; until you become familiar with this product, apply only 1 pound per 100 square feet.
You can also use blood meal as a side-dress, applying it around the base of plants.

Alternatives to Blood Meal

Fish Fertilizers: These are made from the by-products of fish processing, including bones, scales, and skin. They are high in nitrogen, phosphorus, and potassium.
Feather Meal: This is composed of the ground-up feathers of birds at poultry processing plants. It is similar to blood meal in that it provides almost exclusively nitrogen.

Bone Meal vs. Blood Meal

Blood meal and bone meal are both organic, slow-release fertilizers that come from animal products. However, they have different nutrient profiles and uses:

Blood Meal: Supplies nitrogen, promotes healthy foliage growth, applied to spring-flowering bulbs in spring.
Bone Meal: Supplies calcium and phosphorus, promotes flowering and healthy root development, applied to spring-flowering bulbs in fall.

How to Use Blood Meal Safely

Follow the application instructions on the package.
Avoid overusing blood meal to prevent excessive nitrogen levels.
Apply blood meal away from pets and other animals to avoid attracting them to your garden.

Tips for Optimal Use

Use blood meal to amend soil or deter pests on a small scale by purchasing small, inexpensive packages.
Use blood meal as a side-dress when plants show signs of nitrogen deficiency, such as yellow leaves.
Monitor plant growth and adjust the frequency and amount of blood meal applications accordingly.

Understanding Soil pH and How to Raise It

Soil pH and Plant Growth

The pH of soil, a measure of its acidity or alkalinity, is crucial for plant growth. Most plants thrive in neutral to slightly acidic soils (pH 5.8 to 6.5). However, some plants, such as azaleas, rhododendrons, and blueberries, prefer acidic soils (pH 5.0 to 5.5), while others, like cruciferous vegetables and columbines, can tolerate slightly alkaline soils (pH 7.0 to 8.0).

Soil Acidity and Alkalinity

Soil acidity is not static and can change over time due to natural or human-induced factors, such as excessive rainfall, decomposition of organic matter, and the use of high-nitrogen synthetic fertilizers. Soil acidity below pH 5.0 can hinder plant growth, necessitating measures to increase soil pH.

Testing Soil pH

Before altering soil pH, it is crucial to test it using a pH test kit or meter. This test will determine the current pH level and guide the appropriate soil amendments needed.

Methods to Raise Soil pH

Limestone

Limestone, or garden lime, is the most common soil amendment used to reduce soil acidity. It is ground limestone available in various forms, including pulverized, granular, pelletized, and hydrated. Pulverized lime works fastest but can clog, while granular and pelletized lime clog less. Hydrated lime raises pH quickly but requires careful handling due to its reactivity.

Dolomitic Lime

Dolomitic lime contains both calcium and magnesium, unlike calcitic lime which only contains calcium. Both types of lime neutralize soil acidity equally, but dolomitic lime is often sold in pelletized form.

Timing of Soil pH Amendment

For a vegetable garden, soil should be amended in the fall or winter before spring planting. For established plants, such as hydrangeas, lime can be added in early spring, late spring, or fall. Avoid adding lime during wet summers, as it requires water to react and takes time to change soil pH.

Factors Affecting Soil pH

Rock Type: Acidic granite rock contributes to acidic soil, while alkaline shale or limestone contributes to alkaline soil.

Rainfall: Frequent and heavy rainfall leaches alkaline elements from the soil, making it more acidic.

Organic Matter: Accumulated leaves, pine needles, and other decaying organic matter can also increase soil acidity.

FAQ

Blood Meal: A Versatile Organic Fertilizer and Pest Deterrent for Healthy Gardens