Vanda losing buds

[cmg.env]

I have a neighbor that is "hooked on orchids". They have a number of Vandas growing in their back yard down here in Tampa Fl. For some reason, they have a number of plants that after shooting out a spike...........it falls off. It grows to about 2 inches, turns yellow and falls off. At first I thought, well maybe that little cool spell we had over the winter was effecting the plant........well we are well into our summer and the plants continue to drop spikes. They are well cared for, watered every other day, fed once a week......the leaves and roots look great. They are hanging under a crape myrtle tree which allows filtered sunlight to get through. The plants apear to be doing great.....it's just that they drop their spikes. Any ideas????

Thanks in advance for any help,
Chris

[bkim]

Any signs of rot? Are they watering the spike?

[E-Jag]

More sun. More water.

_____________________
E-Jag

[digitalgate]

any record of drop in humidity? My vanda blasted when humidity drop below 60%.

[Orchid_Sense]

Vanda likes high humidity and generally needs to be watered twice everyday. Watering frequency can even be more if you are having a very dry environment and not potting the Vanda in any medium.

[cmg.env]

They don't water the whole plant they focus on the root system. Down here in Florida.....the humidity is really high with the exception of a few months in the winter. They have one vanda that has blasted 3 times.

[digitalgate]

then temperature is the cause of it.

[kmarch]

Without meaning to single any one out in particular, it seems like there's a lot of diagnoses being given without havign all of the facts regarding this situation.

Other than "very high" do we actually know exactly how much humidity this orchid is being grown in?

Do we know what the day and night temperatures are?

Other than the generic "vanda" do we even know exactly what kind of orchid this is?

I understand and applaud everyone's desire to render assistance, but how can we give useful or even accurate advice without knowing all of the factors involved?

[NancyG]

Since you are from Tampa and similiar environment to mine I'll share what is going on with my Vanda's. Last year they were gang busters this year the very same thing that you describe has happened to almost all of mine. They start a spike and then turns yellow and falls off. I have been treating them for thrips. Nasty little bugs that you can't see. I went to a talk on bugs and deseases at the Redland Orchid Show and the speaker described the condition to a tee. Thrips are very hard to get rid of. If this is the case with yours, good luck.
Anyone with suggestions, greatly appreciated,
NancyG

[Brooke]

Thrips are about the size of this - but you have to actually see them in a bloom to ID them. They do crawl rather fast inside the bloom IF you can get the bloom to open.

The damage they do can be so bad the bud might be consumed prior to any opening. They "suck" the juice out of the buds and blooms. It shows up particularly bad in purple or red blooms as blotchy color. The damage is much less noticeable on a yellow, gold or cream/white color. If the bud is large, prior to it opening it will look like someone is sticking pins through it from the inside out.

Here is a link showing thrips damage on a phal bloom.

Big Leaf Orchids • View topic - Bumps on an Unopened Bud

It is treatable IF you do have thrips. Google Conserve - we have used it for thrips that love daylily blooms.

Brooke

[cmg.env]

Thanks for the input. There are a couple different vandas being affected.....however the purple, Robert's Delight, is the one that has lost multiple spikes. I will look futher into the possibility that Thrips may be the problem.

Thanks again,
Chris

[jerrymeola]

I am only an hour south of you and I would go with the thought that it is not enough water. I base this on the fact that you said the buds turned yellow and fell off. This is a sign of heat stress.

When thrips attack (and it is a problem I fight as well) the buds turn brown and dry up. It is a good rule to treat your plants regularly for thrips. They are not hard to control if you understand them Thrips have a three day life cycle so you must treat 3-4 times over a ten day period or you will not stop them.

I use Worm Tea as an organic cure which also helps the roots to retain moisture. In addition to its safety factor, I like that I can spray Worm Tea on the buds and opened flowers at the same time without damaging the flowers. I treat the entire shadehouse twice a month. In the chemical poison group, orthene or malathion will work.

I would increase watering and treat for pests on a regular basis. It is usually too late when you see the pests and you would probably need a jewelers loop to see them when they first hatch.

[cmg.env]

Thanks again for the help. This forum is a valuable tool.....what did we do before the internet???? Killed a number of plants I suppose