Potting Soil & Nutrients
Before I start off with my question, I wish to give some introductory information
I am a new gardener (starting with container gardener on the roof as I don't have any garden space) living in the hot climate of Saudi Arabia in Al Khobar (these days the highest temperature over here exceeds a bit above 100F - Ranges from 75-103 and expected to remain that way until mid of October). The lowest temperature will be 50F in January.
Not much options for me with the potting soil over here. When I read discussion or articles about container gardening I hear a lot about Miracle grow and Liquid fertilizers and potting soil being fertilized or not. Bone meal, blood meal etc. etc. Frankly I am not able to understand how this works.
The people at the local nursery are also not educated enough. They just follow what they have been following for ages without much thought on NPK, Secondary and micro nutrients etc. So there isn't much local help either.
After that introduction, my question is, I have access to two brands of potting soil. One of the potting soil says that it is enriched however it can be fertilzed with a liquid fertilizer once or twice a week. It also says it is suitable for planting vegetables. The other information available on it is 95% organic matter, Ph 5-6, Ash content - less than 5%.
The other potting soil (according to German standard - as claimed) is a bit more sophisticated whose constituents are described on it as follows:
91% Organic dry matter, moisture content 70%
N,P,K - each more than 0.21%
and then a list of secondary and micro nutrients described as PPM.
I am growing vegetables - starting with tomatoes, pepper and cucumber and as the weather gets a bit cooler, with peas, carrots, potatoes - all in containers.
My question is how to transplant the small plants that I buy from the nursery into the pot? Should I just transplant it in the potting soil without any fertlizer or should I add fertlizer also at the time of preparing the container for the first time? How often do I need to fertlize? When does fertlization start? Or is fertlization not required or required very late when the fruits set it?
The local nursery guys tell me to transplant the plants in the first one and put fertlizer after 1 month - once a month - by just sprinkling on the sides of the plant.
Btw the way fertilizer options are also quite limited here and we have either 100% composted cow manure or NPK pellets, The nursery guy is recommending using cow manure.
Also can you help me better understand how much NPK and other secondary and micro nutrients are required in a container of lets say 1 gallon? As a percentage of the total soil? or some other way to understand. This German standard potting soil says 0.21% each of NPK. Does that mean that NPK required only about 0.63% - which would make around - well it would make are 0.25 litres approx for each gallon of soil. Is this what is required in reality? It feels so less.
It would be a great help from the GW community to help me out in this area. I will certainly appreciate it.