How do you feed your plants? Do you use an EC meter? Do you give them an occasional flush with water? Do you top or bottom feed?
Firstly, we should all be using an EC pen to measure the amount of fertilizer in our water, an EC pen or truncheon (EC stands for Electrical conductivity) will measure the amount of salts in the water which you add as fertilizer (Fertilizers are salts). The more fertilizer you add, the greater the EC.
Now think of your plant as a very quickly growing person, when it's young it doesn't want a lot to eat so we set our EC at roughly 0.5 -0.8, then as the plant matures through late veg and early flower we would like an EC of around 1.0 - 1.4. During peak flowering (Adulthood) we will increase our EC to 2.2 maximum (depending on how the plant is feeding), from then on it is recommended to reduce your EC or amount of fertilizer as the plant's metabolism starts to slow (think of this like an old person who eats much less as they get older). This will help you if you flush your plants at the end.
This type of plant centred feeding is much better and more cost effective over the long run than giving your plants the same feed throughout its life. You should think of your EC meter as a speedometer, without one how will you know how fast you are going, similarly without an EC pen, how do you know how much your plant is taking up? In our opinion, an EC pen should be your next priority if you don't have one.
To finish off, when you start using an EC pen, you will be able to more accurately feed your plants, measure runoff concentration during a periodic flush and have better control over how your plant grows.
We highly recommend Bluelab for accuracy and the 2 year guarantee they offer on all products. (http://www.npktechnology.co.uk/products/bluelab-ec-pen)
Hope this has been helpful, please comment with any questions if you have any below.
The NPK team