Ever wondered that before planting a new vegetable or fruit in your kitchen garden or small lawn, you’d like to carry out a simple soil test but don’t have enough money or energy to visit a soil research institute or agriculture university. These experiments are safe, and do not require any scientific expertise.
Observe test- Yes, just look at the soil in clear lighting with your bare naked eyes. A general rule is that the darker the colour, more the organic content in soil. If the soil is rich dark grey, its good in organic content. If it’s yellowish, then you have a drainage problem. Reddish colour and its various shades depict good drainage.
Estimating Soil Carbon Content- This one was taught to us by our soil science teacher. Soil carbon is a good estimation of the organic content that your soil has. To cut the crap, it is a simple estimation of how fertile your soil is. Select a small, convenient amount of soil sample from your garden and weigh it. It doesn’t have to be a sophisticated weighing scale as long as it is accurate. Keep in mind that the soil site you select is the one where you will actually plant something. Don’t go around digging under a tree or near a sewer line. Now take some petrol from your scooter or motorcycle and spray it onto that soil sample. Light a match and burn it and that is it!
Weigh it again. Subtract and bingo, there is your soil content. Difference between the weights is the organic content or soil carbon because what else will burn except the carbon.
Precautions for accuracy-
Scrap away all the soil once you weigh it. If you leave it sticking behind, result will have high degree of error. Use a fire extinguisher, don’t burn yourself. Don’t sprinkle liberally. Remember, it’s an experiment, not a bonfire. Take random six to seven samples and take the average for better accuracy. Take the soil from appropriate depth, at least a minimum of four inches. Remove any mulch, organic matter, dead leaves that are on top of the soil. Use clean equipments, whatever you are using, tray or small spade to dig it, everything should be clean.
Soil Organisms- You don’t need to actually handle earthworms for this test, just count them. For this test, dig a hole in your garden soil. Count the number of earthworms you come across. Generally, if for every random sample, you get more than three earthworms, its good otherwise, add some nutrients to your soil.
Water holding capacity- How much water does your soil hold? Add a small amount of soil sample and mix it with water in a glass. The glass should be made of glass, don’t use a steel one! Now shake it well. Add as much water as you want, doesn’t matter. Now leave it for 6-8 hours and let it settle down.
If your soil is full of clay, then you will find there are many lumps of particles concentrated at the bottom. Sand will have clear water with all soil at the bottom. If water is mostly clear and larger particles are at the bottom with tiny ones at the top, then you are lucky for you have loamy soil (best type of soil).
Testing ph- Ideally, soil shouldn’t be either highly acidic or highly alkaline for most crops. Add some vinegar, if you see a lot of fizz, your soil is alkaline. And if on adding baking soda, it fizzles a lot, it means it is acidic.