In the arena of gardening, I have little doubt that the nutrient Calcium feels a tad underappreciated. Besides being the fifth most abundant constituent in the earth’s crust, plants use (by weight) more calcium than any other nutrient in the ground. It’s critical for cell division. Plants are big into cell division, especially fast growing species like tomatoes, sweet potatoes, corn, and many other vegetables. Despite all this, calcium is rather ignored in the NPK world that we live in.

  Every plant needs calcium, however, and lots of it.

  To quote Agronomist Dr. Arden Anderson,:

    “It [calcium] is the foundation of all biological systems and is the component that gives the living cell its capacitor characteristic via it’s place in the cell membrane. Without the proper capacitor characteristic, the cell’s communication system functions poorly, resulting in cell degeneration, disease, and eventual death.”

  Ok, so that was a little over the top for me, but any paragraph that ends with the words ‘eventual death’ deserves careful consideration.

Garden Problems Associated with Calcium

 Lack of calcium in the soil shows up in many ways. Blossom-end rot in tomatoes is calcium related. As are bitter pit in apples and cavity spots in carrots. Many sorts of fruit deformation can usually be tracked back to calcium deficiency. Some other things to look out for are Necrosis of young leaves, short brown roots, increase in fungus problems, weak stems and just general stunted growth. Basically general garden suckage.

  All this stuff is really bad, but most often the result of limited available calcium is just lack of full potential. Most soils have the calcium required to avoid the terrible problems mentioned above, but obtaining that optimum level can really help your garden out.

 Calcium and pH

  pH does not indicate level of calcium availability. Read that again. This is probably one of the biggest gardening and farming myths in the universe.

 While it is true that most acid soils have lower available calcium than most alkaline soils, pH is about the hydrogen ion concentration. The idea that it’s an indicator of calcium availability is just, well, not true. In fact, as ph rises, calcium becomes less soluble. Added calcium (in some forms) can certainly move the ph scale higher, but so can a boat load of other cations like magnesium and potassium. Excesses of these nutrients can actually reduce calcium uptake in plants while still raising the ph.  So just forget about pH for the moment, k?  Seriously.

Adding Calcium to Your Soil

 So how does one figure out whether one needs calcium in their soil or not? A soil test of course! Try to get a fleshed out soil test with % Base Saturation values. While no ideal range exists for all soils and all situations, I’d wager that if your %Ca is less than 40%, than you want to add some. If you don’t get CEC and Base Saturation stuff on your soil test, have a talk with your county agent or local farmer to see if calcium is generally lacking in your area’s soil as total soil calcium is not a good measure of much of anything without the Base Saturation values. If you have no idea what CEC and all that junk is, talk to your county agent for a lot longer then you planned or wait for a post on the subject right here at Growing Groceries.

 One thing you must realize is that calcium and magnesium especially have a very close relationship. When one goes up it reduces the availability of the other. Plants need both of these so it’s more important that they are at the ideal ratio rather then having the ideal volume of one at the expensive of the other. if you have a Calcium/magnesium ratio of over 5:1 (five parts calcium to one magnesium) then likely you’ll experience magnesium deficiency, so don’t overdo it.

 If you’re like me, you view soil testing as a bother and don’t want to have to number crunch calcium/magnesium ratios and such. In this case the best way to add calcium to your garden is compost. Most compost is relatively rich in calcium and you can make sure of that by adding lime or eggshells to your pile. Since compost is relatively balanced, you don’t have to worry about over applying calcium and screwing things up.  Another no-worries approach to adding calcium is to find an Organic calcium foliar spray that you can spray directly on the plants. This is also a good way to test your calcium availability math-free. Spray a few plants throughout the season and leave a few others alone and see if you can spot a difference.

 If you want to add a calcium source directly to your soil, here’s a list of some of the more common Organic sources

• Limestone- Calcium Carbonate (CaCO3). This is the most common form of calcium found in garden centers. Unless you have very low magnesium levels, do NOT use dolomitic lime, as it contains around 6% magnesium. Calcitic Lime is best. However, Calcium Carbonate will raise pH. So if you already have a high ph, stay away from lime.

• Gypsum- Calcium Sulfate. Gypsum, for reasons I don’t really understand but hear repeated all the time, will not raise soil pH like lime will. This is a great source of calium for those with high pH and low calcium availability.

• Bonemeal- Bonemeal is a great, if a tad expensive, organic fertilizer that contains nitrogen and phosphorus as well as 18% calcium with a negligible pH effect.

• Soft Rock Phosphate- Great stuff. 35% calcium as well as an amazing phosphorus source that’s highly soluble (unlike bonemeal)

• Aragonite- Calcium Carbonate. Seashells. ‘Nuff said.

• Wood Ashes- Have a wood stove? Wood ashes make a great fertilizer for acid soils. Use like lime, but double the amount. Wood Ashes are about 45% calcium carbonate. It also contains a nice little bit of potassium

  Always remember to follow the directions on the bag when applying any fertilizer, organic or not.

Today we have a guest post from Mandy at GardenMandy.com

Introduction To Composting

  Composting is the decomposition of organic matter, such as vegetables, manure or once living things.   Decomposition is performed mostly by bacteria.  There is home composting and industrial composting.  Though the process is basically the same between the two, the techniques will differ.  Composting itself is a fantastic additive to houseplants and offers extra nutrition to gardens.  It is an excellent natural way to recycle kitchen waste and to reduce the amount of garbage sent to public landfills. 

 Composting is not a new innovation, recently conceived in a laboratory somewhere.  As you walk through any forest, you will see the natural process of composting taking place every day.  The process starts when leaves and twigs fall to the ground, build layers on top of each other and begin decaying.  The roots of trees and other plant life then feeds off the decaying layers, as it is returned into the soil.  Composting itself is extremely easy and natural.  Early human races made piles of food wastes, as a way to rid themselves of their garbage.  What they discovered was these piles became habitats for seeds that were unintentionally and then intentionally planted there. 

 Composting today can start the same way, on the most basic level.  Simply make a pile of unwanted biological material, somewhere in your backyard.  You can also build a composting bin by using unwanted wood, such as wood pallets or recycled wood.  There are also commercial composting bins you can purchase.  But why go to the trouble of shopping for a bin, when keeping it simple is the most fun and least costly?

How Compost Helps The Earth

 Composting is a fantastic way of reducing the amount of waste sent to public landfills.  Landfills have been known to produce high amounts of greenhouse gases. These gases do not remain contained in landfills, but escape into the atmosphere. Greenhouse gases are no longer equated with the common sources of  planes, cars, and manufacturing plants. 

 So how does it differ, if biological waste decomposes at a landfill or is used at your home, as a source of a compost pile? When biodegradable materials decay at landfills, a mixture of greenhouse gases are produced and over half of the gases produced are methane based.  At home, the source of the compost decays with oxygen.  When the compost decays, carbon dioxide is produced rather than the more potent methane.  When you compost at home, rather than send these materials to a public landfill, greenhouse gases are then reduced. 

 So what are good materials for composting?  It is not as simple as just saying anything with a carbon or nitrogen base.  Common elements for composting include leaves, sawdust and wood chips, paper, cardboard, manure, fruits, vegetable (yes, even if it’s just their peels), teabags, egg shells and grass cuttings.  Even if you decide not to consider the toxins spewing into the atmosphere from landfills as a reason to compost, at least consider the money you will save, by using natural compost to feed your lawn and garden rather than buying the synthetic commercial brands.