PLants in various conditions that may need repotting.

[JKeys]

I'm a new user to this site, hoping to get my orchid questions answered.

My orchid collection consists of few plants. I have four. I made some mistakes a while back with these plants, and I need to know if I should repot them.

Both plants I repotted after receiving them.

Brsdm. Fangtastic Bob Henley 'Kalapana'-the bulbs and leaves are all mostly healthy. I received the plant in spike in July of this year and the flowers bloomed very nicely. The plant came in a 4" pot. I repotted after it bloomed... in an 8" pot. Now, the plant is pretty healthy still, although the newer bulbs have a few wrinkles, they are in pretty good condition. However, all of the roots that are visible are brown and mushy. Should I repot or wait until nest season for more flowers?

C.Nancy Off 'Linwood' AM/AOS-I have two of these orchids, both fairly large sized, with 10+ pseudobulbs. However, soon after they flowered they both aquired fungus gnats, as well as mysterious tiny black spots under the leaves. The flowers recently withered, and both plants are sending out new growths, and one is sending out new roots. The reason I want to repot is that lots of the visible roots are dead and mushy.

Thanks for your help!

[Gazpacho]

That sounds awful familiar. I've done that. The 8 inch pot was probably a mistake. The roots were used to filling a 4 inch pot. Moving it into a larger pot means more potting mix and consequently much more moisture and much less ventilation. If the roots are all mushy then there's nothing feeding the plant. The couple of phals I have in this condition I've repotted into a pot with much higher ventilation (plastic pot with grid holes in the sides). I put some rooting hormone on the roots first, then packed the pot with damp spag moss and put the whole thing in a plastic bag and moved it to the warmest part of the house, on an east window.

I don't know how that will work out but I have my fingers crossed.

I bought some expensive orchid potting mix with trace elements and stuff all built in. soon after using it, I saw a zillion little black flies.... Fungus gnats. I sprayed the adults, leaves and mix with a systemic chemical called acetamiprid (in a spray bottle per-mixed with water from the grocery store)... And it seems to have done the job. There were some hatchlings which I've hit with pyrethrum based spray.

Today I bought an anti fungal to add to the next watering.

The two that have new leaves and roots must be happy. I'd treat with anti fungal and keep doing whatever it is you're doing. I'd repot the troubled plant back to a smaller pot.... But then, that could be wrong.
Gaz

[JKeys]

ok thanks.

[cbuchman]

I agree with the smaller pot. Be sure to use a clean (sterile) cutting instrument to remove any soft/mushy roots when you repot. I don't have much experience with the fungus gnats, but Gazpacho's advice sounds pretty good.

[silken]

I agree that going from a 4 inch pot to an 8 inch is likely too big. If the roots are rotting, you likely can't afford to wait and should re-pot now. Newer growths are usually not wrinkled, The older ones often are and the new ones are plump so you don't want to lost the new growth's roots to rot. Any time roots appear to be rotting is a good time to un-pot and find out why.

[trdyl]

For your Brsdm., you should put it in a smaller pot as soon as possible. These should dry out within a couple of days after watering.

The Cattleyas should only be repotted when new roots are starting to come out from the new lead. Also when choosing a pot one allow one large enough room for a couple of years new growth when using a bark based medium. The same goes for the Brsdm. as well.

You may want to try LECA, expanded clay pellets, for your medium. This will not break down and will allow maximum aeration for the roots. Over potting is not so much of a concern with this type of medium.

[JKeys]

Thank you all. I am going to be doing some repotting tomorrow.

[JKeys]

Just repotted the Brassidium. Here is the picture after the repotting:
[IMG][/IMG]

[silken]

Looks good! It could be just the colour in the photo, but the leaves look a very dark green which likely means it could use a bit more light.

[JKeys]

ok, I will try and move it.