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The Effects of Oyster Shells

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Oyster Shells contain a unique balance of the nutrients essential for life. This is why, as a soil amendment, it is ideal. The major components of Oyster Shells are protein polysaccharides (a carbohydrate) and minerals including calcium, sodium, magnesium, copper and iron, all which are necessary for photosynthesis (the manufacturing of chlorophyll) and plant stability. Oyster Shells 'sweeten' soil, decreasing acid PH and enhances microbes and bacteria needed for plant growth.

What Is It?

Oyster Shells are ground to a fine powder for use in gardening. This allows for easy absorption by a plant's roots for distribution to the body of the plant. Using Oyster Shells is a good way to get a basic vitamin and mineral blend without having to buy several soil additives. Cultivated plants are dependent on their growers for adequate nutrition, so adding oyster shell powder to your soil will result in healthier plants and more abundant yields than using only manure.

Where Can I Find It?

Crushed or powdered Oyster Shell comes mostly from overseas countries such as China or India. You can find this product retailed locally at any hardware store or garden center. If you can't find it as a singular product, you may have to ask a customer service person for help, as Oyster Shell may an included ingredient in another product such as soil gypsum.


Container Gardening: make your own potting soil for flower pots and patio containers. A standard mix of peat moss, sand, composted cow manure, vermiculite and Oyster Shell will give you a rich medium for your plants. Very little Oyster Shell is needed to feed your plants; only a tablespoon or so per gallon of soil should do it.

Traditional Garden Plots or Landscaping: the large quantities needed for projects such as these will require wheelbarrows or troughs for mixing. Follow the manufacturers recommendations or contact your local Agricultural Extension Office for advice from an agent.

In both cases, make up your soil or the amendment mixture a week or so ahead of when you will be ready to use it. Keep it turned and wet (but not saturated). This will give beneficial soil microorganisms time to become established and multiply.

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