How often do I need to upgrade flower pots?

Depends on what you mean by upgrade. Flower pots can be used until they break and die. Clean them between different plants or if you had a plant get a disease of any kind and make sure you include bleach if it had a sick one in it. As far as when you need to put a plant in a larger pot, it will become root bound and will not behave as well as it did before, just like when a child needs bigger shoes! Make sure you check on the type of plant, as some like to be root bound and may not like you until it gets root bound in the pot you put it in. When a plant needs a new home you should only go up one step in size. When you buy plants to put in your pots they are usually root bound. That is what you plant should look like when it needs to be repotted in a new pot. I wouldn't wait until it is that severe, but that is the easiest way to describe it. Slip the plant and soil out in one piece and it should tell you if it needs to be repotted. Hope this helps!

What do you mean by "upgrade flower pots?" Repot your plants? I repot my plants when they grow out of their current home. And generally repot all plants about once a year or so with fresh potting soil for optimum results. Hope this helps!

Are you talking about the plants inside or the actual pot if you're doing replanting every year I would probably change the dirt and possibly wash the inside of the pot out and check it for damage or mold

I agree with Naomie. I will say, that I can be a little lazy with the new dirt part because I plant a lot of petunias in pots around my yard, patio, on the tables, etc. I don't always change the dirt once a year and the new ones do fine. As a matter of fact, I have 2 large hostas in planters that fit into holes the ends of a bench. I haven't changed their dirt for years and they keep coming back and look so pretty. I did notice this year, that they are a little smaller so this may be the year they'll get fresh dirt.

Depends on the plant. Some do well when "pot bound" meaning lots of roots. Others like space. Check each plant online.

You should upgrade to a larger pot when you see that the root system for your plant is getting crowded :) But don't upgrade by more than 2 sizes UNLESS you are adding plants into the pot with it. Plants like room for their roots to spread and stretch but not too much. It would be like taking a child from a toddler bed and putting them into a kingsize bed ... just too much extra room to feel snug and comfortable ;) Hope this helps :) Thanks for asking Hometalk.