Beginners Guide to OTG - The 2nd quarter.

This is part 2 of 4 of the series of ‘A beginner’s guide to Organic Terrace Gardening’.

Soil and Nutrients

Plants need nutrition to grow. You don’t survive only on water or one particular type of vegetable; the same goes with plants. Plants need air, light, warmth, water and nutrients for their growth.

Nutrients from air and water are Carbon, Hydrogen and Oxygen.
Nutrients from soil are of 2 types ... 

1. Macro Nutrients 
• Primary Macro Nutrients are Nitrogen (N), Phosphorus (P) and Potassium (K), commonly referred to as NPK. These are the major nutrients usually  lacking from the soil first because plants use large amounts of NPK for their growth and survival. And hence need to be added at regular intervals.
• Secondary macro nutrients are Calcium (Ca), Magnesium (Mg), and Sulphur (S). There are usually enough of these nutrients in the soil so fertilisation is not always needed.
2. Micro Nutrients.
• Boron (B), copper (Cu), iron (Fe), chloride (Cl), manganese (Mn), molybdenum (Mo) and zinc (Zn). These elements essential for plant growth which are needed in only very small (micro) quantities

The mix of soil and the various ingredients (detailed below) is commonly referred to as potting media, media and potting mix. All the above nutrients are initially provided by the soil when you make a fresh potting mix. However over a period of time, these are used up by the plants and hence you need to keep adding them to the soil in different forms. Remember not to overdo and to make the best out of resources that are easily available and procurable.

A short video about the importance of soil.

Red Soil

You can get red soil from any good nursery; the nearer the better, as it can be really heavy. A cement bag of red soil costs around Rs. 30-50.

Cocopeat / Coirpith

This is made from coconut husks and has absolutely no nutrition in it, but has excellent water retention capacity. It is added so that the container retains more moisture and it reduces the weight on your balcony/terrace. Cocopeat is available in a few forms:

1. Compressed block: In 1 or 5 kg blocks, it looks like a solid brick. Soak it in water and it expands in size. This simple video explains how to break down a cocopeat block easily. A 5 kg block expands to around 25 kgs loose ready to use cocopeat. A block is easy to carry. A 5 kg block costs around Rs. 100-150.

2. Loose, uncompressed powder: Difficult to carry as it is sold in 25-30 kgs sacks.

Pic a. Cocopeat block.

Pic b. uncompressed cocopeat

Compost

This is a broken down and decomposed form of kitchen waste, dried leaves, cow dung, etc. The process of decomposition takes about 6-8 weeks. There are additional supplements available which help speeding up the breaking down process. These are called as 'accelerators', like sour buttermilk or ready-to-use "microbes powder". When this breaking down process is done with the help of a specific breed of earth worms (common name: Red Wiggler; scientific name: Eisenia fetida or Eisenia andrei), the end result is called vermicompost. This is one of the most important items, that makes your garden organic. On an average, compost costs approximately Rs. 5 - 25 a kilo. Composting is quite a vast topic and like gardening, one will learn only when one takes a leap into composting.

Vermi Compost Pics courtesy (Uma H)

Cow dung

Cow dung is mainly used as manure in agricultural farms. Do not use fresh cow dung as they contain harmful bacteria and can kill the tender roots. It should be allowed to age/mature for at least 30 days before using in any form or for any gardening purpose.
If you have a source for naati/country cow, then nothing like it as there is a significant difference in the cow dung properties from these types of cows, as compared to the hybrid/jersey cows.
Try to locate a cow shed in your vicinity. Cow dung cakes are sold for about Rs. 5-10 per piece.

Horse/Sheep/Goat dung

Similar to cow dung, Horse/Sheep/Goat dung is also useful as manure for enriching the potting mix. Usually available at nurseries.

Neem oil/powder/cake

The Neem tree is considered to be very sacred in India.

Its oil, combined with water, is usually the first organic and natural pesticide used to get rid of insects from your plants. After the oil is extracted from the seeds, the leftover is the cake.

The cake is further processed to be converted into a powder form. Its quite a laborious task to break down the cake into a powder form manually. There is a chance of adulteration while converting the neem cake into neem powder. So, if your source of neem powder is credible, then its a good idea to use the powder. Else its a safe bet to use neem cake directly. The powder is used mainly while preparing the potting mix, as it helps to avoid root based infections, like fungal infection and nematodes.

Neem oil costs about Rs. 150 for 250 ml, Neem cake about Rs. 40 per kg, and Neem powder about Rs. 20 per kg.

Sand

The sand used in construction activities s sieved to get rid of larger pieces. Adding sand prevents the potting mix from becoming too clayey, and helps the potting mix to be well drained. Like cocopeat, sand has no nutritional value. Though there are exceptions and a few folks are growing leafy vegetables with beach sand. Overall, the purpose of adding sand is for maintaining a well drained potting mix.

Mixing it all up !

Proportions of each of these components depends on the plant you are growing, experience and availability. An average mix is 1:1:1 of compost : cocopeat : red soil, plus a handful of neem powder + sand. Some plants need a loose mix (well drained), so put less red soil and more sand. Mix up all these ingredients well. There should be no lumps. Move this mixture into a container. 

Do use gloves throughout this process. And also when you are handling different types of manure/dung. Sometimes, it may be uncomfortable to do gardening activities with the gloves on. In such cases, do wash/clean your hands thoroughly, as the soil, compost, etc tend to get stuck under your nails.

It is very important that there is no water stagnation, so ensure that the container has drainage at the bottom. In case you are using a container with more holes or holes larger than a marble, cover them with coconut husk or a small piece of net or something similar. This helps the water to drain, but not the potting mix from the pot.

Fill the pot till about 4/5th of its depth. This is so that you can add more compost and nutrients in the future.

Once the container is filled, pour in water lightly until all the potting media gets wet and water starts to seep out of the holes, and your container is ready!

Picture of fresh potting mix for sowing sambar onions. This has more of red soil and vermi compost, less of cocopeat.

AND ... do remember to take a couple of deep breaths to smell the earthy potting mix !!!

This is part 1.
You are currently on part 2.
This is part 3.
This is part 4.

Disclaimer :  All prices mentioned are estimates.