When to repot a Phalaenopsis - Orchid Board

orchidkilla · #1 02-17-2011, 11:14 PM

Hello, as you probably guessed I'm posting on these forums because I need help with my orchid. I was looking at general guidelines as when to repot my Phalaenopsis, yet, I lack the experience to make an accurate judgment about my plant. I've gotten some conflicting advice and I'm wondering which is right:

Some websites say when the roots are climbing out of pot its time to change pots and/or media. Other sites say its fine for the roots to be climbing out of the pot.

History: I've had my moth orchid for about 5 weeks. About one week ago my orchid leaves started yellowing. My orchid is in a room with a south window and southwest window. My orchid has four large leaves, and the center leaf facing away from the south window, towards the southwest window is the most serious.

When I first got the orchid I took the orchid out of the larger pot and left only the plastic pot. I also took a look at the roots and most of the roots were green with a few almost brown roots. Since I've gotten the orchid the roots seem to have climbed or grown further out of the pot, while other root still wind around in the bottom. Now the roots not only are an inch or two above the pot but now are climbing out towards the spot between the south-west and south facing windows. The climbing roots are 5 inches long. None of the roots are poking through the holes at the bottom.

As for the flowers, the orchid was blooming with 3 flowers when I bought it from Costco. There is only one spike with 8 buds on the flower spike. I just noticed that the 6th bud is starting to open up. Yet, for about 5 days the first bud looks wilted.

Hard facts: one spike, 8 buds, six buds are flowering, one is wilting.
substrate: mixed bark
watering frequency: one a week with diluted fertilizer.
Pot diameter: 6 inches
largest leaf length: 10 inches
length of roots dangling over side of pot: 5 inches
temperature outside: low of 10F high of 50F and windy.
Inside temperature: 55F in day and 65F at night.

I'm not sure how bad my plant is, I looked for blacked leaf tip and black spots and found none. Is it good for my roots to be dangling five inches over the side of my pot? Should I panic now?

camille1585 · #2 02-18-2011, 04:05 AM

First of all, welcome to Orchidboard!

The dangling roots are nothing to worry about, and in fact are perfectly normal for Phals. They're called aerial roots. Phals in the wild grow attached to trees, getting lots of air and moisture around the roots. Since potting isn't 'natural' for them, a lot of Phals grow these aerial roots. Some plants grow them more than others, I have Phals with aerial roots nearly a foot long. You can help these roots along by misting them with water.

As for repotting, if there is no emeregency then generally the best time for repotting is in the spring when the plants are starting to grow again. Phals like to be snug in their pots, so when you repot if the plant can fit in the same pot, then use it again.

Sometimes it's better to repot sooner. Sometimes newly purchased plants don't have very healthy roots, especially the ones potted in sphag. In that case it's better to repot (and clean up the dead roots) ASAP to save the plant.

Discus · #3 02-18-2011, 04:50 AM

People also generally recommend you repot when you see active (new) root growth around the bottom of the plant - that means there are new roots there to quickly grow into the newly repotted plant. Of course, in an emergency, you do it anyway.

I have one phal that just won't quit flowering - I want it to so I can repot it, as I don't want the new buds to drop from the shock - the sphagnum it's in is looking quite dubious.

You will occasionally see the lowermost leaf turns gradually yellow and drops off - this is usually after one or two new ones have grown (or are starting to grow) out the top. If they're all going yellow, something is definitely amiss.

Val · #4 02-18-2011, 07:52 AM

Quote:

Originally Posted by Discus

I have one phal that just won't quit flowering - I want it to so I can repot it, as I don't want the new buds to drop from the shock - the sphagnum it's in is looking quite dubious.

I repotted a flowering phal because I discovered a moss-ball in the center of the pot (several days after I bought it) - and had absolutely no bud blast or anything afterwards. I'm terrified by moss and I was willing to take the chance.

I think most phals don't mind being repotted when in bloom. Anyway, saving the plant is more important than keeping the flowers. A healthy plant will bloom again and again.

Just my

Val · #5 02-18-2011, 08:02 AM

Quote:

Originally Posted by orchidkilla

watering frequency: one a week with diluted fertilizer.

There's no standard watering frequency. It depends on your conditions (air humidity, temperature, light). But the transparent pot is your best friend, and the roots will tell you when they need to be watered. Green roots are wet, they don't need to be watered. When at least 95% of the roots are silvery white, it's time to water your phal.

The same phal in the same spot on your windowsill will need to be watered every 15-30 days in mid winter, but every 3-5 days in mid summer. The roots will tell you.

Daethen · #6 02-18-2011, 08:30 AM

The top leaf going yellow is not a good sign. Did you take the plant gently out of the pot to look at the roots? You may have some rot going on in the center of the root ball or maybe some bugs eating the roots. It could also be sunburn if it is getting too much direct light. Post a few more times so that you can upload a picture and we can all help you more from there.

silken · #7 02-18-2011, 10:56 AM

I am wondering if it is getting too much sun. Is it sitting on a window ledge or in the middle of the room? If it is on a south or SW window ledge, it is likely too much unless you have trees shading it or a sheer curtain or something. One way to tell, is to touch the leaves when the sun is shining on them and if they are warm, it is too much. Phals don't like direct or bright light. Maybe that is why the leaf is turning yellow and flowers wilting. Without pictures, it sounds like the roots are pretty good.

orchidkilla · #8 02-19-2011, 05:00 AM

I just watered my orchid. I used about 3x the usual concentration of orchid fertilizer. I used about 1/2 Tbs diluted in a quart of water. When I picked up the orchid's pot to make sure the roots were silvery, and the pot felt light, the wilting leaf fell off. I noticed the leaf was 2nd from the bottom of the four leaves.

The leaf was yellow with some orange and almost red coloring around the base of the leaf and edges of the leaf closer to the base. On the underside of the leaf I noticed the leaf was tan and yellow. The tip of the leaf, away from the break is still a lush green. The only black specs rub away easily, as if they are dirt. The leaf feels leathery to the touch.

As for sunburn, I don't think so, my orchid is protected by glass block windows on the southern side. Also I put my orchid underneath a small tropical tree, a split leaf philodendron. The orchid pot is on top of the soil for the philodendron, so the tropical tree protects my orchid. There is about eight other plants that protect my orchid in the room. I tell that I've watered my orchid enough, when water spills out the drainage holes and into the split leaf's soil.

camille1585 · #9 02-19-2011, 06:27 AM

The fact that the yellowing seems to have started from the base is not a good sign. That usually indicates crown rot, likely from getting water in it.

Since your plant is in bark, watering until water comes out the bottom is likely not enough water. Bark holds nearly nothing, so water runs through pretty quickly. You either need to pour a large amount through the pot or soak it in a bucket for 10 minutes.

For the fertilizer, you say that you watered with 3 times the normal amount?? Unless this is a typo, watering with that much fertilizer is usually not a good idea. Many orchids are not very salt tolerant and if at each watering a lot of fertilizer is used, then it is going to burn the roots.

orchidkilla · #10 02-19-2011, 05:32 PM

Hmm, interesting I was using the algorithm for watering my potted tomato plants for my orchid. I never thought the bark substrate would hold less water than soil. As for the fertilizer, yes I put about 1/2 a tbs rather than 1/6 or 1/8 a tbs, which is what I was doing for the last 5 weeks.

Orchids are complicated, I was thinking that I did sometimes water right in the middle or crown, since with tomato plants and most other plants you are supposed to water at the base.