Phalaenopsis orchid with droopy leaves, shrinking flowers, and sickly buds
 

My oldest phal orchid, which I've had for maybe 3 or 4 years, has started having some issues. Every year, the flowers that bloom get smaller and smaller. This year, one of them won't even open completely. Some buds turned purple and stopped growing. It even started growing a new flower spike, but the bud at the tip has turned purple.

On top of that, its leaves are very droopy, and most roots have died. I removed all the dead ones.

Could this be a nutrient deficiency or dehydration? Thank you in advance for any help!

You said it yourself, most of the roots have died. You can't grow a healthy plant without a heathy root system. What are your growing conditions? Temperature, humidity, what type of pot, how often do you water/fertilize, has it been repotted since you bought it, growing on a windowsill? We need to know some facts before we can help you.

My orchids are on a screened-in porch on a windowsill. Where I live, humidity is relatively high, especially right now. Temperature is in the 70s-80s. It has been repotted once, maybe last year. The pot is clear plastic with slits in the sides so the roots can breathe. I water it whenever the roots are pale, so probably around once a week. I stopped fertilizing it for a while, but restarted last week to give it some extra help.

Yes, the photo shows a dehydrated plant. Now we need to figure out why it is dehydrated.

Thank you for the help! I figured at least part of the issue was dehydration with leaves in such rough shape. Most roots died, so my best guess is that. Another thing to consider is my substrate, which I should have researched more before buying. It's entirely wood chips, so it retains no moisture at all. Would you recommend a well-draining substrate, or something that holds onto moisture a little better? Not sure on that one. Here's a picture of the roots:

At this point I would cut the flower spike to keep the plant from spending energy. Put it in a mixture of bark and sphagnum moss keep it out of direct light. The reason why I would make it a mixture is to not loose the roots that you currently have. water once per week with some kelp.

Let's back up... you said most roots died. How could you tell they were dead?

Staying moist is not bad for most orchid roots. Not having air is the problem. If your medium had substantial air spaces you could water frequently and there should not be a problem. Medium without air spaces is the problem.

The roots you show in the photo above from this morning should be adequate for that plant. Is that the plant after you trimmed the roots, or before?

At your temperatures, in a pot with slits, it is possible once per week watering was enough. But given how dry the plant looks it is more likely you didn't water often enough.

To me, those roots don't look great, but don't look horrid either. Once a week may not be enough water - To determine when to water, consider watering well, drain well, and then weigh the plant on a kitchen scale or postal scale. Do the same the next day etc. When the rate of weight loss declines (flattens out) because there is not much more water to evaporate, it's time to water again. ("How often" is affected by media type, temperature, humidity, the pot... your mileage will differ based on all of the factors, it's not something that fits a formula.)

Those floppy leaves are likely to stay floppy even if the plant is now getting adequate hydration, but new leaves will be normal.

Personallly, I don't see any particular problem leaving the spike. It's mostly done as far as flowers go, but the green stem can serve as a reserve for water and nutrients. If it turns brown then just cut it. But I doubt that it is putting any stress on the plant, and might even be helping.

So sorry for the misunderstanding! Those are the roots after I removed the dead ones. The ones I cut off were brown, dry, and completely shriveled. The orchid had many more roots before that trim.

Brown, dry and shriveled roots may still be alive. I can't usually tell. Despite what is spread all over the Internet I recommend people not cut off old roots. I only remove those that come off with a gentle shake.