Question
QUESTION: hello I recently repotted all my orchids.a soil mix recomended by a rep from home depot.all of them started turning yellow.I checked the roots and almost all were rotting.i put them back in the mix I had them in and im still losing them.the leaves are rotting in the middle of the plant.I cut off all the dead stuff befor planting them.????help Diana

ANSWER: Diana, I hope the Home Depot representative recommended the proper potting mix for repotting your orchids. Both Home Depot aand Lowes carry Miracle Grow ord Better Grow Brands Orchid Potting mixes.  The Better Grow is recommended by the American Orchid Society and it is definitely preferable as it consists largely of medium size fir bark.  This allows for both better drainage and air movement through the potting mix. You will need to soak the Better Grow Orchid potting mix prrior to use as fir bark repels water when dry.  The Miracle contains some slow release fertilizer but has too fine of a particle size for most types of orchids. The key to the growing of new roots (and then leaves) is to use the right type of orchid potting mix in the right kind of pot.  Your pot should have lots of drainage holes in the bottom (I prefer plastic pots for phalaenopsis).  Do not have your pot in standing water as these pot and potting mix need to drain freely.

As I recall, Home Depot provides a limited warranty on their orchids and you should check into that if you're interested.  Unfortunately, Home Depot just sells orchids and does not grow them.  That means that they usually do not have personnel with expertise in growing them, In my experience, most of the orchid plants they sell already have the beginnings of root rot and should be repotted as soon as feasible.

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QUESTION: Dear Wayne I did all of what you said before writing .My problem is that the leaves are turning liquid in the very middle of the plant, is this a result of the root rot or something new? I didnt have these problems until I reppoted them with the fine bark mix that was recommended. I went back to the large bark when I reppoted them again because of losing them.also I purchased some orchids from Thailand those are planted in moss and seem to be doing well. thanks Diana

Answer
This sounds like something new-- called bacterial crown rot.  This is usually the result of getting water in the crown of the plant during watering.  It is very serious. Un-pot the plant and soak the entire plant in a solution of Physan 20 (1 Tbs/Gal) for 10 minutes.  Repot in fresh mix.  Withhold water for a week.  Spray weekly with Physan 20.  Be sure to water earl in the day trying to avoid getting water in the crown.  By watyering early, there is time to dry off before nightfall.  I also like to use a small fan on the day of watering to dry the plant more thoroughly.  Follow the cautions on the container of Physan 20.