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Soil & Amendments

A Guide To Understanding Soil

We have all walked down the store aisle wondering, “Hmm, which soil should I choose this time?” With all the different mixtures out there, it can be confusing.  What are all the amendments in these mixtures and what do they actually do? I have a few answers that may help you along your way.

San Diego Hydroponics carries a large selection of soil mixtures to choose from. Here’s the breakdown on these soil mixtures and what their amendments do.

FOX FARM has a few different soil mixtures that seem to be popular with the local folk. The first is Ocean Forest, which is what I call the ‘old stand by,’ it has been around for a long time and it is the most popular soil amongst local farmers here in San Diego. Its ingredients include:

Forest Humus: A natural forest compost containing organic matter from the forest.

Sphagnum Peat Moss: Sphagnum is actually live moss taken from a peat bog, whatever that is. Peat moss can hold large quantities of water, about twenty times its dry weight, making it a very useful amendment.

Fish Emulsion: A product rich in Nitrogen, which will keep your plants nice and green.

Crab Meal, & Shrimp Meal: Both products are both rich in Nitrogen and phosphorus to give you a more balanced feeding.

Earthworm Castings: Earthworm Castings are well known to increase vigor and provide an excellent source of plant food.

Fossilized Bat Guano: Bat Guano is bat feces, which is high in phosphorus.

Sandy Loam, Perlite, Granite Dust: Sandy Loam is composed of sand, silt, and clay and helps retain water. Perlite is a volcanic glass that holds water while, at the same time, aerating your soil. Granite Dust is a good source of potash, in laymen’s terms: potassium and  also provides calcium, iron, magnesium, phosphorus and trace elements and micronutrients.

Norwegian Kelp Meal: Dried raw seaweed tends to contain about 1% Nitrogen, a trace of Phosphorus, and 2% potash, along with Magnessium, Sulfur, and numerous trace elements.

Oyster Shell: Oyster shell is an organic pH stabilizer.

We also carry another FoxFarm product called, Happy Frog. Happy Frog also contains, forest humus, sphagnum peat moss, perlite, earthworm castings, bat guano, and oyster shell. However, it also has three amendments that Ocean Forest does not have: Humic Acid, Mycorrhizae, & Lime. Humic substances are formed by the microbial degradation of dead plant matter, which help to break down nutrients making them more readily available for the plant. Mycorrhizae is a beneficial bacteria which helps to prevent bad bacteria such as pythium or root rot.  It also increases the plants uptake of water and nutrients. Lime helps to stabilize PH.

Roots Organics is another soil company that we carry. It is relatively new but the locals seem to like it a lot because they keep asking for it.

Roots Organics Greenfields is an ocean nutrient based potting soil mix for both the vegetative and flowering phases of mature plants. Its ingredients include coarse peat moss, compost, perlite, worm castings, bat guano, fish meal, crab meal, kelp meal, Pumice, a volcanic rock that increases aeration, Fishbone meal a natural by-product of the fishing industry. Fish bones are cooked and ground to create a high phosphorus fertilizer perfect for flowering and fruiting plants. Soy bean meal, a substance high in nitrogen and Feather Meal, a common by product of the poultry slaughter industry, which is also high in nitrogen, but releases more slowly than other amendments.

Roots Organics Natural & Organic Potting Soil is an indoor & outdoor gardening medium whose ingredients include: peat moss, perlite, pumice, compost, mulch, worm castings, bat guano, kelp meal, fishbone meal, soybean meal, feather meal, and oyster shell. It also contains  Glacial rock dust, which has trace elements from glaciers. Prilled rock phosphate, a slow release phosphorus amendment. Greensand, an element mined from deposits of minerals that were originally part of the ocean floor. It contains about 3% total potash, along with iron, magnesium, silica and as many as 30 other trace minerals. It may also be used to loosen heavy, clay soils and improves plant health. Leonardite is a low rank coal derived from terrestrial plant matter which contains Fulvic Acid, Humin, and Humic Acid. Alfalfa Meal, which is high in nitrogen and Coco Fiber allows for more aeration while also retaining water.

Roots Organics formula 707 is designed for greater water holding capacity. It contains less perlite and pumice. Ingredients include coarse peat moss, coco fiber, compost, perlite, humus, worm castings, bat guano, fishbone meal, soybean meal, feather meal, and kelp meal.

I hope this information will help make your soil choice easier when you come into the shop. Thanks for reading.