How do I properly repot an orchid. I am in zone 9b

It depends upon what type of orchid it is. Your particular zone often has nothing to do with it. Unless the type of orchid you want to repot happens to be a terrestrial type, these would be suitable to grow in some type of soil based mix.

Most orchids we grow like Phalaenopsis, Cattleyas and Dendrobiums are epiphytes. Epiphytes grow on something for support like a tree branch and can not survive potted up in soil. Why? Because air must be allowed to circulate around their roots at all times.
Within the "Orchid Forums" here on this site, we have numerous thread or 'stickies' that deal with questions and answers such as yours. You could read through the sticky on growing "Supermarket Orchids-Phalaenopsis", if this is the type that you have. I personally started a thread on how to repot a Cattleya type orchid or Bulbophyllums. But the method depends somewhat on what type of orchid it is.
THE KEY IS- NO SOIL.
There are several people here who can offer you their opinions on how to best grow certain orchids. Look at the label with the plant for a name or send us a good image of the plant so that we might assist you further. BigBill
Welcome to the Orchid Forums!!!!

Phalaenopsis once potted up properly can be grown outside in Zone 9 but they require shade, no direct sunshine. They like temperatures from 65-85. They need to be watered before they go bone dry. They like good air movement and a little plant food 3 or 4 times a year.

BigBill
Here is a photo of my orchid… I have 3

boxers1 said:
BigBill
Here is a photo of my orchid… I have 3

Wow

That is a beautifully grown Phalaenopsis.
That sticky we have about growing supermarket orchids-Phalaenopsis is something that you should read from beginning to end because it would just be filled with good information about growing them and repotting them.
In addition, on the AOS American Orchid Society webpage, www.aos.org, there is a section at the top called member benefits or something like that. If you access the pull down menu within, you will find culture sheets on how to grow the major types of orchids. These are downloadable and printable pdf files. Print the one on growing Phalaenopsis.
Lastly if you click on my name within one of my posts, you can access the threads started by BigBill. I did a pretty nice tutorial a while back on how I repot Phalaenopsis complete with instructions and pictures. The best time to repot them is after they finish blooming which would be in the spring. But in reality, you can pot them up anytime. They respond very well to repotting and suffer very little set back.
Good luck!!!

Thanks so much. I will follow your advice to the letter. These orchids have been a ton of fun. I feed them weekly with a formula from MSU /I think… I freeze it in old ice cube trays. I am sure you are familiar with the product, one for well water which I used to have and one for municipal water