Small Spaces and Containers – Maximizing Growth and Yield

Pot up early and often for maximum growth and yield

In a post in 2009 I  posted pictures where I compared plants in various sized containers, and put different numbers of plants in containers.  Smaller containers result in smaller plants and smaller yields.   Multiple plants in containers lead to smaller plants and smaller yields too.  The trick is getting the smallest sized container that will allow your plants their maximum growth in the space you have indoors.  A rule I have read is one gallon of soil/medium for each foot of plant height.  This of course depends on the species of plant you are growing, but is a good rule of thumb. 

I have noticed another problem with small containers.  Many growers start several plants in small containers and then put them up into bigger containers as they grow.  This is a good way to pick the best plants too, especially if you are doing any plant breeding.  Remember; if you breed plants don’t get mired in mediocrity.   If you keep a plant in a small container, and it gets root bound, even when you pot up the plant it will not grow to its fullest potential.
The take away message, always keep your plants roots growing.  Once the roots start to twist around and around in a container, they send out hormones to the plant that resources are going to be limited, and growth should slow.  When you pot up the plants, they will grow more, however not as much or as big as plants that were never root bound.
You should pot up your plants as early as possible.  Here is what I noticed this semester; I had two groups of plants.  Group one, I potted up as soon as roots got to the bottom of the container.  I started with small containers, then went up to one gallon then three gallon containers when I put them onto flowering.   The second group, I kept in small containers for an extra two weeks, then put them in one gallon containers for two weeks longer than the first group.  My idea was that I could get two flowering cycles in one semester.  What I noticed is that the first group plants were all tall and bushy and the second group plants were shorter and single stemmed.  It seems that when a plants roots are not allowed to grow, the hormones that slow growth somehow prevent the plant from ever reaching its full potential.  I think this would be like if a child does not get all its nutrition, it will never be able to reach its full potential, even if has all its nutrition met as an adult.

Pot up early and often for maximum growth and yield

Good Growing,
Dr. E.R. Myers

Read my post on suggested container sizes for plants