Bugs destroying Vanda’s flowers

[KikaMaggie]

Hello everyone,
Finally my Vanda bloomed this Autumn for the first time, and the flowers were nice for 1 week at most, and then some tiny bugs or mini caterpillars have eaten the back side of the flowers. It was happen also to other vanda’s spikes and to some phal flowers.
Does someone know how to fix it?
Thank you very much!
A nice week for you all.

[Clawhammer]

Looks like you have thrips, sorry to break this news.

Do you have access to the pesticide spinosad (Conserve)?

[KikaMaggie]

Thank you very much for your reply.
I can’t find this pesticide for home use here in Portugal. Are the “all purpose” supermarket pesticides efficient?
May I spray the flowers and spikes?
I’m hoping to save the other vandas that are all with spikes, and thrips…

[Keysguy]

It does look like thrips to me as well.
I use orthene because I grow outside but here is a really good source of information with more options.

Orchid Pests

[Clawhammer]

Originally Posted by KikaMaggie

Thank you very much for your reply.
I can’t find this pesticide for home use here in Portugal. Are the “all purpose” supermarket pesticides efficient?
May I spray the flowers and spikes?
I’m hoping to save the other vandas that are all with spikes, and thrips…

I couldn't comment on the pesticide without knowing the active ingredient.

Isolate the plants that have thrip damage.

Can you tell us more about your growing environment and your collection?

I don't believe thrips will be able to pierce vanda leaves to feed, only flowers and buds. Also, if they are hanging and not potted that will be an advantage as thrips spend one of the stages of their lifecycle in the soil.

I have had thrips in my growroom for about 20 months. Right now I have 60 catasetum with leaves, it is impossible to eradicate them, so I am using a "knock down strategy" until my catasetinae are leafless and I actually have a chance of eradication. I have found it possible to bloom an infected plant by isolating it and treating it separately while the plant is in spike. Once the flowers open the pesticide really takes a toll on the flowers worse than thrips, but if you isolate and treat the plant during spike there is a chance of a normal bloom.

---------- Post added at 03:05 PM ---------- Previous post was at 02:57 PM ----------

While you are looking for a pesticide...

Try submerging the whole plant in a bucket water for 15 minutes or so.

Also, use a strong squirt gun to spray spikes to attempt to reduce thrip population (all life cycle stages except adult will be invisible to the naked eye). They get into the buds if the infestation is severe and will cause bud blast. If you already see damage to the buds (like the one in the pic) the cause is hopeless.

[Fuerte Rav]

Hi
Rbarata is probably the best person to advise you on available pesticides as she also lives in Portugal.

I haven't found any of the pesticides recommended by our US friends, here in Spain, but I'm in a remote corner , perhaps mainland have more choice. I've looked online as well.

What I use is a mix of Neem oil and horticultural soap in lukewarm water in a pressure sprayer. Completely cover the whole plant and flowers every 3 or 4 days for about 3 weeks. I use 10ml hort soap + 5ml Neem oil to 1L lukewarm water.

Warning: the only orchids I've used it on are Phals. No experience on other varieties but I can't see why it wouldn't work for Vandas.

You can't correct damage that has already been done but hopefully you can prevent more damage from occurring. I treat my Phals about once a month now in case more thrips have arrived - I don't want to wait to spot the damage!

Good luck!

[KikaMaggie]

Hello everyone, thank you very much for your messages!
Actually thrips are a new enemy for me! From the very first day I learned it’s name I have lost the first infected Vandas blooms and also 4 phals. It was a complete infestation….
What have I done? I have put all of them back to the balcony ( cold nights now, 10-14C) and have bought all I found against bugs.
My vandas are in wooden baskets and phals are mostly mounted in wood and in baskets.
I’m sending photos of the plants and the sprays I have now and would really appreciate if you could help me to choose which one is better.
Thank you very much again!

[Clawhammer]

Originally Posted by KikaMaggie

Hello everyone, thank you very much for your messages!
Actually thrips are a new enemy for me! From the very first day I learned it’s name I have lost the first infected Vandas blooms and also 4 phals. It was a complete infestation….
What have I done? I have put all of them back to the balcony ( cold nights now, 10-14C) and have bought all I found against bugs.
My vandas are in wooden baskets and phals are mostly mounted in wood and in baskets.
I’m sending photos of the plants and the sprays I have now and would really appreciate if you could help me to choose which one is better.
Thank you very much again!

Beautiful setup and plants.

I would isolate anything in bloom and treat those separately. Thrips will most likely be concentrated there.

My Spanish is not great but I don't think the active ingredient of those pesticides were displayed in the pics.

[KikaMaggie]

Originally Posted by Clawhammer

Beautiful setup and plants.

I would isolate anything in bloom and treat those separately. Thrips will most likely be concentrated there.

My Spanish is not great but I don't think the active ingredient of those pesticides were displayed in the pics.

Thank you.
These are the ingredients in each formula.
There are also dendrobium and phals leafs eaten by trips.
May I put the plants inside again after treating? Isn’t it also toxic for children?
Have a nice day

Abamectina e Piretrina

Acetamiprida

Vegetable fat acids with sulphur and potassium

Detametrina, abamectina e tebuconazol

[Clawhammer]

Originally Posted by KikaMaggie

Thank you.
These are the ingredients in each formula.
There are also dendrobium and phals leafs eaten by trips.
May I put the plants inside again after treating? Isn’t it also toxic for children?
Have a nice day

Abamectina e Piretrina

Acetamiprida

Vegetable fat acids with sulphur and potassium

Detametrina, abamectina e tebuconazol

Acetamiprida is a neo nicotonoid which will be effective against thrips as a foliar spray. It is systemic but won't accumulate in the flowers to a magnitude that it is effective systemically.

Vegetable fat acids with sulphur and potassium is also known as a insecticidal soap. This will also kill thrips on contact.

1.) Give each plant a 15 min soak fully submerged in water
2.) Isolate infected plants that have flowers / buds and treat separately
3.) Treat every 3 days alternating between these two pesticides. Do your best to coat everything including the growing media and basket with the pesticide
4.) Repeat for 3 weeks