Don't throw the baby(ies) out with the bathwater would be my advice. If a scale infestation automatically meant the destruction of a plant there would be very many fewer orchid collections on the go. Likely you are past the point of Q-Tips and alcohol and need to go to systemic relief for your problem. You might find after a summer outdoors that Ladybugs and other beneficials have reduced the size of the problem for you. Good luck.

H

hi, sorry to hear about your battle with scale. what has worked for me it that i use scotch tape to take the scale off the plant, then i saturate all the leaves and medium with neem oil (1/2 teaspoon neem oil, drop of soap in 1 litre of warm water). may have to repeat the procedure a few times to get rid of them. i use tape because the scale gets stuck on the tape and so it does not fall into the medium so it cannot go back on the leaves again. good luck.
sue

I like to make sure that I get all the little buggers and their eggs. Alcohol spray will get any that it contacts, then I follow with Orthene WP , spraying thoroughly x 3 at 7-10 day intervals. Scales are not just a pain for the hobby growers--commercial growers are on constant lookout to avoid serious infestation. Thankfully, I have had no problem since I started using Protek regularly.

Bear in mind that you have to treat the medium also as eggs may be hiding there, and if you only treat the top of the plant they will keep on hatching.

The only formula I've ever had to use: one-third ordinary Spray 409, one-third 91% alcohol, one-third water, with about a teaspoon of dishsoap. On a bad infestation, usually the third application separated by 10-14 days gets any stragglers.

-Bruce C.

P.S. In a pinch, when I didn't have any formula mixed up, I've used Ant & Roach Spray and a paper towel. Works just as well, and makes those leaves really shine!! As a disclaimer, I only used the Ant & Roach Spray on tougher-leaved plants, like cattleyas. Not sure if it would be OK on soft-leaved plants.

I use similar to above, only less ingredients. 1 part 409 of insecticidal soap (HD), 1 part alcohol and 8 parts water. This mixture is innocuous enough to use it freely. I brush off the visible scale and then spray 3 times, 3 days apart. I also spray the nearby plants even if they don't show scale. This gets the emerging young who are most vulnerable, I don't think you can kill the eggs and you don't want the little buggers to form their hard shell. I think 11 day interval its too long and gives them a chance to do just that.

Nick

I had some scale last fall. I had it off and on for over a year. It just loved my catts. yet left all of my paphs (which is the majority of my collection) alone. I tried a few nasty chemicals but let me tell you what really put them to rest. I went threw my whole collection of about 900 plants and picked up each and every one of them. I sprayed Sun Oil (which can be any light horticulture oil, that you can get at Home Depot or Lowes). The only horticulture oil I could find this time was in a sprayer that you hooked to your house. I bought it and opened it up and mixed 1 tablespoon per liter of H2O with a small squirt of liquid hand soap. I sprayed each and every plant in every direction that I could. Then all the ones that I thought I even saw an indication of scale I put on one shelf. Then I sprayed just those plants heavily in one week. Then I did it again for 4 weeks running. Haven't seen another one since. Worked for me and it should for you. Another trick if you only have a small collection is to repot them all in fresh media. When they are out of the pots spray them with the mixture of horticulture oil. Especially pay attention to the underside of the leaves and any small places where new growth it pushing againg the old growth.

Bob in Albany, N.Y.

I've had good results with a good cleanup as described above, and then spray every week for about 4 weeks with Bayer rose and flower insecticide. I did have one very unusual experience this year with scale. I have a potted abutilon that had some intermittent scale this spring in the GH. I was keeping an eye on it and treating it as necessary, waiting til it could go outside, but one day I noticed it was covered with scale. So I threw it on the compost pile. A couple of months later I noticed it had leafed out again (roots buried in compost pile), had buds, and no sign of scale. Not sure what was going on in that compost, but I pulled it out, repotted it, and it has been blooming ever since. Who knew that compost could cure scale????

My guess would be that the compost pile contains quite a few more beneficial insects and other life forms than other garden areas, and they helped by dining on the scale. I've noticed that volunteer plants growing on my compost pile are incredibly healthy, with no signs of pests or diseases!

Thanks to everyone who posted a recipe for curing scale! I recently noticed a few scales on the underside of a hippeastrum leaf, and they're grown alongside some of my orchids. I would hate for the scale to infest the orchids, and so, I'll be using one of the remedies above!