1 vanda dormant? another green tip burn

[rcheng]

Hi,
I have 2 air vanda, a yellow and purple. The yellow vanda was growing well with 2nd bloom, 2 weeks after the last bloom dried and drop off. There were >30 green tip air roots. About 2 weeks ago, the green tips roots began to stop and became white instead, when i switched to soaking the vanda with rain water for 4 hours almost daily like what i did with chlorine free tap water. Then, i switched back to soaking it in tap water which was kept for 1 night to allow chlorine to evaporate. After 1 week i noticed 1 or 2 roots became green tips only. i think the vanda is in dormant state. Appreciate advices?
The purple vanda was growing slowly soaking with chlorine free tap water and fertiliser, like the yellow vanda. After weeks, many green tips appeared. >30. However, about 1 or 2 weeks ago I noticed that 1 and then 4 or 5 green tips began drying and then became black. Appreciate help to let me know what went wrong?

[WaterWitchin]

Providing a picture of the roots would be helpful.

[estación seca]

Are you in Singapore? Is it indoors, or outside? What are the temperatures and humidity in your growing area?

Dying root tips are often caused by low humidity, inadequate watering or bugs. It sounds like you are watering enough. Cockroaches and snails like to eat root tips. Tiny bugs called thrips ("thrips" is both singular and plural) also cause root tip damage. I don't know whether there are thrips in Singapore. The classical appearance of thrips root damage is a root that begins growing again from the damaged area, leaving a narrow dark brown ring of damaged tissue with a normal root growing beyond that.

[rcheng]

Hi,
i attached a picture of the root system of purple vanda which is rather badly hit with black root tips. (not sure how to bring the attachment to this message)
Green circled the good green, dark yellowish or brown root tips while the black ones i think are bad.
Questions are what is the cause and how to stop the attack.

I hang the yellow and purple vandas in the common balcony and they are separated by about 2 meters. temperature in sg is 25 deg Celsius to <30 ish. At night about 23 to 25ish. Humidity is rather humid in sg about 70%. i soak these vandas in water for about >4 hours almost daily. they were doing well for about 3 to 4 months then they start to develop tips issue about 2 weeks ago. fyi - i did experiment soaking them in rain water which i collected for about 2 weeks and this is when things start to turn that bad. But i did the same to the repotted cyms but they seems to be doing well. i saw about 2 green root tips started to grow when i remove some surface spagnum moss (about 1/4" layer, the rest are bark, charcoal, peat moss and perlite beneath the spagnum)

[estación seca]

Your growing conditions sound good. I don't think you need to soak them that much. People in southern Florida have similar temperatures and humidity. They water once or twice a day with a hose. You could dip the roots into the water for a few minutes until they are thoroughly wet.