Contents
In today’s post we will look into the importance of calcium in gardening and 6 easily available organic sources of calcium for plants, And What out of these really work and Why? Then, Finally Two Gardening Hacks or Tricks to get instant supply of calcium to your plants.
Understanding the Importance of Calcium in Plants
Before we start listing the 6 easy sources of calcium to plants, we will quickly know the importance or the function of calcium in plants. Calcium plays a very important role in the overall growth of plants. It helps in the absorption of major nutrients by the roots in the presence of water. It is essential for the formation and integrity of the plant cell wall and hence very essential for fruit formation.
Signs and Symptoms of Calcium Deficiency
Calcium deficiency can cause necrosis or death of plant tissue at certain parts of the plant, particularly at the tips of fruits and tips of growing leaves which appear like burnt tips. Blossom End Rot Disease seen in tomatoes, peppers, and squashes is the best example of such necrosis due to calcium deficiency. Plant chlorosis or leaf yellowing and stunted growth are also signs of calcium deficiency.
Top 6 Organic Sources of Calcium for Plants
Having said that, now let’s list out the top 6 options or the sources of calcium to plants. If you do vegetable gardening or intend to grow veggies organically in your home or terrace garden, please follow this till the end!
6. Milk
This is the most expensive option and not recommended because most of the ingredients found in milk along with calcium are not required by plants. Like fats, lactose, and proteins are not essential to plants. But, if your milk is spoiled, you may dilute it and water it to your plants or make a foliar spray by mixing it with compost tea, like how we have done this in my previous posts.
5. Egg Shells
No doubt egg shells are composed of calcium carbonate. You know, even one of the hardest things, marble, is calcium carbonate, and also the soft chalk sticks are calcium carbonate.
The point here is if you add crushed or even powdered egg shells into the soil, it might take many months and even years for it to decompose and release that calcium for uptake into the soil. This option is least effective for treating an acute disease like Blossom End Rot or a stunted plant. Perhaps this option of powdered eggshells may be utilized while preparing your potting mix before planting. Another option for instantly providing calcium for plants is to water the plants with the water used to boil eggs. Do not throw away this water. Cool it and water your plants with this. Egg shells release some calcium into water during the process of egg boiling.
4. Bone Meal
Yes! It’s an excellent source of calcium, but the problem is the plants can only get phosphorus from bone meal and cannot utilize calcium from bone meal. This is because of the garden soil pH of around 6.5, which is slightly acidic for most garden plants. And at this pH level, it’s not a good option to use bone meal as a source of calcium.
3. Expired Calcium or Iron Tablets
Are these of any use to the plants? Certainly not for instant supply of calcium, unlike in humans. These are complex binding forms or compounds in these tablets that take time to decompose and release them for uptake by plants. The best way to use these expired tablets is to add them to your compost bin. The final compost formed will be rich in calcium and other minerals.
2. Lime
Agricultural lime is chemically calcium hydroxide. And another variety, garden lime called dolomite lime, is more commonly used and it’s also a good source of magnesium for plants. No doubt, it’s a great source of calcium. The only drawback is it increases your soil pH level to alkaline levels which is not desirable for most plants. Unless you have tested your soil pH and it’s found too acidic, like below 5.5 levels, you can safely use lime for your plants. This pH meter is quite handy and very inexpensive. You can buy it online from Amazon. Well, the dosage of lime should not be more than 1 teaspoon per liter of water or 1 tablespoon per gallon of water once in a while, like once in 3 months. But still, if you want to use this and keep your soil pH unchanged, you have many options – like adding a lot of compost manure to raise the pH or you can mix about 10 grams of alum powder in 1 liter of water to compensate for the soil pH level because alum acidifies the soil or alternately add 1 or two teaspoons of white distilled vinegar into this.
1. Gypsum
Gypsum is one of the best sources of calcium for plants and the safest option simply because it will not alter the soil pH levels. Chemically, it’s calcium sulfate dihydrate. It’s also called lime sulfate. Gypsum is also used in clayey soils to remove soil compaction and improve soil drainage. It drastically reduces the sodium levels or salinity in the soil, which is very important if you are watering your plants with salty or hard water.
The dosage for gypsum is 1 teaspoon per liter of water or 1 tablespoon per gallon of water once in about 3 months. Depending on the container size or the plant size you can safely increase the dosage if necessary.
Additional Calcium Hacks
And finally, the most inexpensive sources of calcium for home gardening: The calcium hacks using chalk pieces, egg shells, and white vinegar.
Chalk Sticks Hack
Chalk is chemically calcium carbonate. You can take white chalk sticks and bury them into the soil while planting your veggies. That’s in the initial stages. This really works wonders for plants like tomatoes, peppers, squashes, eggplants, and almost any vegetable plant. You can bury two chalk sticks per container for these vegetable plants safely if your soil pH is around 6.0. For other plants to provide a slow-release calcium source, you can bury one chalk stick per container.
Vinegar Hack
To treat Blossom End Rot disease or any acute deficiency of calcium in plants, you can mix lime and vinegar or egg shell powder + vinegar to break down the compound and prepare a water-soluble form of calcium that can be quickly absorbed by the roots. Make sure if you use egg shells, sun-dry them for at least two days or microwave them for a few minutes. It’s simple! Just take a handful of egg shell powder or one or two spoons of lime and add the same amount of white vinegar to this. You can see a chemical reaction between calcium carbonate and acetic acid which releases carbon dioxide as gas and free calcium into the solution. You can leave this alone for a few hours and then mix with water and water your plants. This is the cheapest and the best source of calcium for plants to treat acute deficiency. That’s it!
Video Tutorial showing all the Sources of Natural Calcium for Plants below:
7 comments
truly you have provided very nice information, thanks for sharing
I absolutely love your YT channel and all of the useful information therein. As a non-native English speaker, you write your scripts in a wonderfully concise way, with no extra words to waste the viewer’s time! You have great passion and skill for teaching and empowering others. Your work is very much appreciated.
CJ
Do flowering house plants need calcium
Thanks for the last one. Now we can use eggshell.
Very nice presentation. Please update latest informations through you tube.
You say to add chalk pieces to the plant or dissolve eggshells in vinegar. What about dissolving chalk sticks in vinegar, would that also work?
Thank you very much for the free gift of knowledge you shared in this article