Cactus and Succulent growers have a start on other Phalaenopsis beginners. They are less likely to kill a plant with kindness.
Those lines on the leaves point to recent stress due to over or under-watering.
Given good growing conditions the plant will probably recover.
Seek out complete culture notes on the net and read some of the past threads on this site. Seeing you are thinking of repotting, search for Phalaenopsis + repotting. Search box is on top of this discussions page.

Thank you for the useful advice. I just lifted up some of the moss mixture that coats the roots and found several important discoveries:

1) The rest of the roots seem green and thick--hopefully healthy (for now)
2) Everything is bone-dry
3) And the oddest discovery: the plant itself is wrapped in some sort of plastic and surrounded by peat moss. It's really firmly placed in there and I have no idea why in the blue blazes someone would do that.

I'm hesitant to water it because I know that orchids need a lot of air flow to their roots, and that plastic looks like it would spell perched water and rot to me. Why would anyone put plastic in there, and how do i get it out?

It all depends on growing conditions. That orchid was raised in controlled glass-house conditions where that medium and container will be fine. Some growers get very good results with spaghnum moss because they get the watering right.
Find those complete culture notes, read those past posts (taking into account where the writers live) Example,the micro climate outside in this particular part of Sydney is zone 10 and outside is a Phalaenopsis Death zone.
Some orchids need a lot of air flow around their roots and Phalaenopsis is one of those.
Anyway, it is all there in the past posts, you have to adapt what is said to the growing conditions you can provide.

I would say that the plastic is there for easy handling/growing at the nursery and when the buyer removes the orchid to re-pot it stays together. I would just remove the plastic as it's going to limit the root growth. A pair of scissors and needle nose pliers should work just fine for removing the plastic. Just be careful where you snip. These guys have been growing on their own for gazillions of years and never needed plastic bags around them, right? If everything is dry it needs water. They grow in jungles where it rains all the time!! Sitting the pot on top of marbles allows for the excess water to drain out. You will have to monitor the water level right after watering. I also place my orchid under the kitchen sink faucet and drown the thing using the sprayer. I spray the leaves to clean them off. Let it drain real good before placing it back onto the marbles. If you use the orchid mix from Lowes you should not have any problem.

Also, I suggest you re-pot into a much larger pot. Give it some room to grow. When repotting remove the plastic....

This post was edited by Toolbelt68 on Fri, Jul 4, 14 at 20:24

I just rescued a similar size orchid from Lowe's for $5!
It too was wrapped in plastic and planted in dense moss, almost soaking. I took it out as soon as I could, re-potted with less moss and removed all of the dead roots (about 40% were rotted, but the rest are fine)

The plant is still blooming but the flowers are starting to fall off. The leaves are in excellent condition!

Since the moss was soaked when I bough it, I will wait until it dries out before watering. Right now I have the plant in a terracotta orchid pot sitting on a plate of moist rocks.

I have a question, would it be recommended to cut the stems down to the base of the plant once all the blooms drop, or just cut above a node on the stem?

You have asked the eternal question and the answer is that the choice is up to you. I tell newbies (and people buying the plant as a cheap bunch of flowers) at orchid shows to cut to a node while the Phalaenopsis experts at the local orchid society cut the spike down to the base.
I've never seen a rebloomed spike on a hybrid at a meeting or a show.
{{gwi:184096}}

Here is a link that might be useful: Cutting spikes

Do not plant this orchid in gritty mix. It is too fine and the roots need air. Look at the size of the root. It is not thin and fine like an cactus root. These plants grow clinging to the side of trees. The root area collects debris such as leaves, mosses, etc. They need an airy mix.

Cut the spike down to the crown. If you grow the plant well over the summer, it should send up new spikes in the fall.

You are in zone 10. That is a warm climate. You could plant the orchid in a medium bark mix with some sphag mixed in (small amount.) The idea is to not allow the roots to dry out completely but not keep them too wet.

Give it a try. Buy some inexpensive orchid mix. These plants should be easy for you to grow and flower in your climate.

Don't worry about the bumpy leaf. The plant appears healthy.

Jane

Thank you so much, everyone! Jane--I had the same hesitations about the gritty mix, so thank you for clarifying. I purchased a medium bark orchid mix today and am repotting it (as well as my mother's, before she kills hers with water) in a larger terra cotta pot with good drainage. Will cut the spike later, as there are two more buds waiting to open, besides the new one which opened today! You all have been so friendly and helpful, thank you.