Choosing Correct Container Size. How? Why?
** I am aware of potential issues with potting into a too large pot (see 3rd paragraph) - my primary question is in regards to knowing if a pot is/will be too small for a plant. This is information that I've searched the forum for but I'm either not using the right search terms or there just isn't a lot of information about it. I feel pretty confident that I'm just not using the right search terms, lol. I can't be the only one who has wondered about this.
As you might know, I'm new to houseplants. I've made up some gritty mix & 5-1-1 (waiting for my coarse perlite to make up more) and have repotted a few plants into the different mixes. I have several more that I plan to put into one of the two mixes but I'm unsure about pot sizes. Most of them are in the same size pot that I bought them in - 4". A few are in bigger pots (either that they came in or that I put them in) the largest is 6", not counting my peace lilies which are in larger pots.
Will I do the plants a disservice if I leave them in the 4" pots? How do I decide what size pot to put them in? I know that with the gritty or 5-1-1 I can put them into larger pots with no issues (except, perhaps, initially more frequent watering). I just happen to have a lot of cute small pots or cache pots and not as many bigger ones.
Right now I believe that if the plant's roots are filling the current pot, it ought to be potted up into a larger size. But what about the plants which might grow rapidly? Of course, except for a couple, I'm not entirely sure which of my plants would be/are rapid growers - but still...
I repotted the Dark Pittsburgh Ivy into gritty mix today. It had a little root system so I felt okay about putting it back into the 4" pot. We'll see how it goes!