Orchid collection dying

[King_of_orchid_growing:)]

Just thought of a 6th factor...

6. What are the temperatures for the growing area?

Day temps?

Night temps?

Seasonal temps?

[orchidvalley]

I agree with Phillip, there may be more going on here. I think you should also check how deep the plant is planted, it looks a little deep in the picture.

[tylerumn]

Hello everyone,

I took a picture of my paphs. (pic. 3) that shows the spread of mites. Surprisingly, the maudie is still trying to bloom. The dens. (not pictured) look fine in terms of having a healthy root system -- they are growing out of the pot and do not appear to be rotting under the bark chips.

I looked at the root system of my cat. (pic. 1 & 2) that was most severely affected by mites. Indeed there is a secondary problem as some of you have pointed out -- mealybugs on the root system. I quickly rubbed some isopropyl alcohol and hope that will temporarily help until I receive the insecticide that I ordered.

As for my growing conditions:

Lighting: 400W HPS
Temp day: ~75 F
Temp night: ~70 F
Humidity: 20

I'm considering setting up my humidifier again despite the ban from my landlord. Alternatively, I could try adding more water trays, but there's so much that technology will take you.

- Tyler

[sastry]

Hi
My paphs and cattleyas are severely infested with mealy bugs and repeated cleaning with alcohol has helped only to some extent and again the pest is bouncing back. Infact i have lost few cattleyas and paphs because of infestation. Other than cleaning with alcohol i have tried carbaryl but not much of relief. Any suggestions please.
sastry

[Zoi2]

The only way I've found to get rid of mealies is to unpot, totally clean the plant with alcohol and repot in fresh media in a sterilized pot.
Joann

[sastry]

Originally Posted by Zoi2

The only way I've found to get rid of mealies is to unpot, totally clean the plant with alcohol and repot in fresh media in a sterilized pot.
Joann

I agree with you Joann but to remove the grown up plant especislly paphs is some what ..... but better than losing the plant. Is not there any systemic insecticide which can take care. I also fine in my place the humidity is quite low and this might encourage the mealy bugs multiplication.

[Gin]

I Don't know what systemics you can find there? usually any that work on Roses is safe for orchids I use one made by Bayer either tree and shrub or soil and turf . 1 Tbs to a gallon , it takes awhile for the chemical to enter the plant spraying the plant with the plain brown Listerine mouth wash will kill the ones already on the plant until the systemic kicks in . ..

[sastry]

Originally Posted by Gin

I Don't know what systemics you can find there? usually any that work on Roses is safe for orchids I use one made by Bayer either tree and shrub or soil and turf . 1 Tbs to a gallon , it takes awhile for the chemical to enter the plant spraying the plant with the plain brown Listerine mouth wash will kill the ones already on the plant until the systemic kicks in . ..

Thanks Gin, we get here Dimethoate which is a systemic insecticide, listerine you mentioned what will be the amount of dilution that i can try imediately, let me see and hope i would be able to control this

[Ray]

Tylerumn - what I see first and foremost are plants that are being grown entirely too dry.

I suspect you have taken the errant recommendations about orchids needing to dry out between waterings far too seriously, and are applying it too strenuously.

You appear to have a fairly coarse potting medium, so air flow to the roots should not be a problem even when the medium is saturated. I suggest that you soak the pots (individually) for about 30 minutes as a means to rewet the bark (staying that dry inhibits its ability to absorb well), then water them thoroughly just before they get totally dry again.

[RosieC]

Looking at those pictures I would agree with Ray that they look far too dry.

Even if you try and dry between waterings they should 'just' dry, not become completely parched. Also water with lots of water when you do water (I either soak or I run lots of water throught the pot).

They key is to realise (as Ray has said in the past) that it's not the water which rots the roots but the lack of air flow which water causes by blocking the gaps. Orchids need water.

I find as a general rule it is best to get a medium mix which dries in 7 days or less and then water thoroughly when it's just dry.

As a slight side note on watering... I strangely have had no luck with watering sooner (ranging from Phals to Dens to Oncidiums) when in bark even though there are plently or air spaces when not yet quite dry. I have found with Hydroton (as a standard medium) I can water before dry and the plants love it. With Hydroton as a semi-hydroponic medium they are constantly wet and love that as well.