Merit systemic may have caused this on my Miltassia - Orchid Board

silken · #1 10-02-2011, 01:48 PM

My Miltassia NOID which I am quite sure is Royal Robe 'Jerry's Pick' is in bloom right now. It had 9 spikes which was every mature PB that hadn't previously bloomed.

I was given this from an acquaintance this time last year with a few of the last flowers still on it. But I quickly found it to have scale. Luckily it was never integrated with anything else in the greenhouse and the problem was contained to this one plant. I re-potted and removed all media and thoroughly hosed the entire plant down in the shower. Then I treated it with Merit once by spraying the plant and the new media since it is a systemic. I have the weaker granular version of Merit and it says use once a year. However a month later I still had some scale, and on this forum I read of people using it for 4 to 6 weeks in a row to successfully eradicate scale. So I did that and the scale is gone and the plant seems very happy and healthy. It must be since I got so many new growths and spikes.

However, most of the flowers are coming out looking very strange. I had photos of the flowers from last year and strangely, usually the last bloom or two on a spike look close to normal. I first thought virus. but the flowers were fine when I got it and it has always been totally separate from any other orchid.

I am blaming the heavy use of Merit and think it will bloom normally next year (I hope). I try not to over use pesticides, but it was a case of eradicate this scale ASAP rather than risk spreading it thru my hobby greenhouse. And once didn't seem to do it.

Attached are several pictures. The first is the last two flowers on a spike that look pretty much as they should. The 2nd is the way the rest of the flowers on each spike look. and the third is a picture of the plant as of today.

I was so disappointed as I wanted to send it to the Calgary show. but it looks like the flowers might be mostly finished anyways before then, so better luck next year

Eyebabe · #2 10-02-2011, 02:53 PM

I am not familiar with Merit, but since it is a systemic, I would think it is possible for it to affect blooms.

If you have a virus test around, it might be worth a check.

silken · #3 10-02-2011, 04:22 PM

I don't have a virus test, and when I checked into buying them, you had to buy so many at one time that it cost a fair bit of $$

It is completely away from other plants simply because it is too large to sit on the table with others, so I eill see what happens with the next bloom, unless I get some virus test kits before that.

camille1585 · #4 10-02-2011, 04:44 PM

If used Merit while the spikes were growing, then yes, it is caused by the pesticide. Imidacloprid is known to cause deformed blooms, and this is something I learned and had to inform customers about back when I had a short job selling pesticides/fertilizers in a garden center.

Eyebabe · #5 10-02-2011, 04:59 PM

Quote:

Originally Posted by silken

I don't have a virus test, and when I checked into buying them, you had to buy so many at one time that it cost a fair bit of $$

It is completely away from other plants simply because it is too large to sit on the table with others, so I eill see what happens with the next bloom, unless I get some virus test kits before that.

I would agree, if you had one handy, then it would have been easy to do.
But given the likelihood it is the Merit, I would not undergo that kind of expense and wait.

silken · #6 10-02-2011, 06:33 PM

Quote:

Originally Posted by camille1585

If used Merit while the spikes were growing, then yes, it is caused by the pesticide. Imidacloprid is known to cause deformed blooms, and this is something I learned and had to inform customers about back when I had a short job selling pesticides/fertilizers in a garden center.

I used it nearly a year ago just after the last spikes were finished. But all the new growths that are in spike now, were just getting started. I still the blame the Merit but only because I used a lot more than recommended on the container.

Ray · #7 10-03-2011, 10:11 AM

I have never seen flower deformation/discoloration caused by Merit, but I have always kept the dosage in the specified range.

POLKA · #8 10-08-2011, 11:08 AM

Ray and Everyone

I have used the Bayer Systemic for Roses (with the active ingredient in Merit = imacloprid (sp?)-- at the recommended rate, and I have had a little of this plight, not a lot, but a little bit. And occasionally I will get some black streaks or spots in the leaves/ stems of some of my catts /epidendrums that were at a sensitive point in their growth.

They grow out of it, both new leaves and flowers return to normal.

I used it on white boisduval scale. And, it seems to work if you treat whole pot. CERTAINLY DON'T USE TOO MUCH PRODUCT ON ORCHIDS. I suppose 1/2 to 2/3 of the full dose would be much better on orchids.

I grow and treated dendrobiums, oncidiums, catts, and cymbidiums. The oncids and catts seemed a bit more sensitive than the others in my case, anyway.

hope this helps

Take care and happy growing
Rex

Leafmite · #9 10-08-2011, 04:35 PM

I'm sorry your blooms were a disappointment this year. I hope you will let us know if they are normal next year.
Good luck for next year's blooms!
Leafmite

glengary54 · #10 10-09-2011, 01:17 AM

Silken - Two things, your plant does look like Milt Royal Robe but it is not 'Jerry's Pick' which is a solid color, there are other clones, yours looks more like the 'Diplomat' clone. From my understanding of Merit, the granules are meant to be used as a dry broadcast insecticide on turf. The granular form is also more potent then the wettable powder form and the ready to use sprays. Given that I think we can safely assume that you over treated your plant and the resulting deformation was indeed caused by that and it will eventually grow out of it.