Member Tips
Bayer Insectacide - Ed Merkle
Two major pests on orchids are mealybugs and scale. The insects hide on
the undersides of leaves and growths and pull the life out of your plants.
They also fasten themselves to flower stems and pull the life out of the
flowers, and their sugary excrement makes a sticky and sometimes moldy
mess on the leaves below. Spraying the adults with alcohol or oils or
soaps will kill them, but they will have already produced young "crawlers"
that travel up to several feet away, on counter tops, under pots, on
neighboring plants, only to return later and re-infest the plant. So,
with this type of treatment you must re-treat every 7 days for a month or
more before getting good control of the problem. If you don't, they will
likely return again and again, providing lots of anguish and frustration,
and even loss of plants.
Recently I began using Merit insecticide in my greenhouse for controling
mealybug and scale, and it works very well. Merit is the chemical named
Imidaproclid, a systemic insecticide. (Yes, its also the ingredient in
Advantage pet flea & tick drops.) It is absorbed by the plant, making the
entire plant toxic to these insects. This is great because this will kill
the crawlers too for several weeks. Merit works well but it is expensive,
$50 for a two ounce bottle of powder...1/10th of a teaspoon per gallon,
which is actually not too bad for someone with a large greenhouse to care
for...but a little pricey for the small hobbyist. Luckily, Merit is also
available for the hobby grower in a product named Bayer Advanced Garden
Rose & Flower Insect Killer. It also controls most of the other insects
affecting orchids such as thrips, aphids, plant bugs, etc. This is a
water-based product that will not harm your plants in the way oils and
petroleum based products can.
This product contains the chemicals Imidacloprid (Merit) and Cyfluthrin,
in a ready to use form...no mixing...just spray it. It can be sprayed
directly on the plant and potting media as a systemic insecticide that has
bug killing action for two weeks to 30 days. The 24 ounce bottle cost me
$4.85 and it will treat up to 35 plants. Its available at Home Depot,
Lowe's, Walmart and many other retail gardening centers.
I've read the label thoroughly and it appears that this product is
licensed to be safely used indoors, with 2 main requirements: 1. It
should not be used in small enclosed areas where the mist would allow
inhalation of the product. 2. You should remove pet dishes until the
product dries and strictly keep it away from fish aquariums and birds.
Children and pets may reenter the area after product dries. There are
other label instructions as well, such as placing the plants in shade
until after the product dries.
While this product is not labeled expressly for orchids, it is labeled for
flowering and ornamental plants, which in a generic way includes orchids.
However, with very delicate orchids I would use some caution to make sure
there is no damage. I've heard from several friends that have used it on
many delicate types with no damage at all.
Here is a link to the Bayer product page...
Bayer
Hope this helps. Remember that you must follow the instructions on the
label. And it is highly recomended that you try it out on one plant first
to make sure that under your conditions it does not harm your plants. It
may or may not damage flowers. I've not seen any damage in my plants
personally, but there is always the possibility.
If you are a novice, you may not realize that a Federal law makes it
illegal to use a pesticide not in accordance with its labeling, and its
also illegal to recommend others to do it, whether privately or publicly.
This is why I mention the labeling and legality issues, because its
important to know that this product is OK.
The Rose and Flower spray is also available in a concentrate form for
re-filling a sprayer.