Water Soluble Calcium Phosphate

Calcium and phosphorus are essential nutrients for natural gardening. Make your own water soluble calcium at home with 2 simple ingredients.

Calcium is as essential for us humans as it is for our plants.  Making your own water soluble calcium for natural gardening or farming is as easy as two simple ingredients: organic fermented vinegar and eggshells.

Calcium and phosphorus are minerals that support the plants during their change-over stage. The time between the flowering and fruiting of a plant (change-over stage) is much similar to the period of pregnancy when essential nutrients are needed to help the next generation of species evolve.

But why even make your own?

Making your own WSC is simple – extract the calcium from something you would normally be tossing – eggshells. If you consume eggs, or raise chickens, then making your own water soluble calcium at home is super easy.  

Eggshells carry lots of calcium carbonate but it is trapped inside the eggshell and needs to be extracted.

Benefits of Water Soluble Calcium

In natural farming, it’s important to add calcium and phosphorus during certain times of the plant development. Calcium is needed during the beginning stages of the plant to assist in strong growth. Phosphorus is important during the period between vegetative cycle and flowering.

Signs of calcium deficiency can be seen in fungal disease and  blossom end rot (tomatoes). Lack of calcium can also lead to pH deficiencies making things more acidic.

Water soluble calcium allows nutrients to be absorbed by the plant much more easily. It’s far superior than the powder form of calcium, as powder calcium needs a longer period to break down before it can be used by plants.

Ingredients needed:

• Eggshells
• Vinegar (alive:  apple cider vinegar, brown rice vinegar)* 
• Mason jar (quart)
• Cheesecloth and rubberband

How do you make water soluble calcium?

Gather the eggshells and give them a good rinse in the sink. Remove the sticky layer in the eggshells – the only thing you want is the calcium.

Allow the eggshells to dry – you can set them in the sun for this.

Toast your eggshells. You can do this any of several ways: with a flame propane torch, in the oven or on a BBQ.

• For calcium only you want the eggshells to be toasted brown (not charred black). 
• For phosphorus you will want eggshells that are charred black.

Once toasted, crush them into small pieces. Or, you can add them to your coffee/spice grinder and whizz to a fine powder. 

(I’ve done both and my preference is the powder, but crushing them works fine if you don’t have a grinder).

Put a quart mason jar on a scale, and tare the jar. Then, add the toasted eggshells. Weigh them – then calculate the “alive” vinegar.  Your eggshell weight x 5 is the amount of alive vinegar that needs to be added.

You can use organic apple cider vinegar, brown rice vinegar or your own homemade apple cider vinegar. You can even use kombucha that has turned to vinegar (and all the sugar has been consumed).   *Do not use distilled vinegar or white vinegar.

Add the vinegar very slowly. The mixture will fizz up quickly, but the foam will dissipate within minutes.

Cover the jar loosely with a lid or with cheesecloth. Let it sit in a dark space for at least 20 days. After 20 days, add a tiny bit more toasted eggshells – if the mixture doesn’t fizz, then the mixture is at its capacity for absorption. 

If the vinegar fizzes, then it still has room for absorption to extract more calcium.

Usage: water soluble calcium and/or phosphorus

Water soluble calcium, or water soluble phosphorus, can be diluted for foliar application. Add to a spray bottle (for a smaller garden) or a larger sprayer (for larger areas), diluted at 1:500. 

Spray as a foliar directly on your plants early morning (preferably before sunrise) for best results.