Question
QUESTION: Hello!  I recently bought my first orchid plant (an Oncidium orchid with white blooms that have little brown spots toward the center of the bloom) at a farmer's market, and since I brought it home the petals of the flowers have started to dry out and brown slightly.  The soil still feels moist, so I haven't watered them in several days, and though I can't see the roots without removing the plant from the pot, the leaves all see to be in good shape - no spots and are a nice, rich shade of green.  Are the blooms just reaching the end of their cycle, or should I be doing something different with the plant?  I'm concerned because it is happening on several flowers simultaneously and began just after I brought the plant home.  Thanks!

ANSWER: Stephanie, I think the flowers have simply reached the end of their cycle.  The potting mix needs to dry out or root rot could occur. Because the potting mix is still wet, this suggests that the potting mix has broken down and retains too much water.  The plant probably should be repotted in fresh orchid potting mix.  You may have a twig  epiphyte called a tolumnia.  If you can send a picture of it i might be able to provide more info on the potting and growing conditions.  Thanks.

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Petals and plant   QUESTION: Thank you so much - I'm relieved to hear that I haven't somehow killed the poor plant before having it for even a week!  I'll definitely try repotting the plant - it feels like it's currently in normal potting soil, which maybe means that the soil has broken down, as you said.  Should I repot in a larger pot or in one the same size as it currently is?  Given that, once the blooms die off and I have to trim them from the plant, do I cut them at the very base of the flower or where the bloom's stem meets the main stem of the plant?  Lastly, should I be fertilizing now, or should I wait until the next cycle of blooms starts?  I've attached a few images of the plant/flowers, so any additional insights would me much appreciated.  Thank you so so much!

Answer
First, on pot size, it' going to depend upon how many good roots you have.  If you have lost quite a few roots, you probably can repot to the same pot (providing it has lots of drainage holes in the bottom).  Otherwise, you may need to increase the size of the pot by an inch or two in diameter.

I recommendd that you cut off the old bloom spike.  This type of orchid does not rebloom on the old spike.

Wait to fertilize until you have new growth.  Then, use either a high nitrogen fertilizer or a balanced fertilizer (ie either a high first number or all three number about the same).  A balanced fertilizer can be used all year at about 1/4 to 1/2 tsp per gallon of water (once it starts new growth until it flowers)