scale on gymno crest

Just a quick question, what is the best insecticide/treatment for scale insects? My Gymnocalycium baldianum crest has some... the small brown type near the growth area. not that many there but i'd rather be rid of them so they can't spread asap. i soaked them and the gymno in confidor but the plant appears to be dormant now so it is not taking up water (therefore systemic can't work) and the contact action of the confidor seems to be repelled by the hard protective shell of the scale.

If it wasn't a crest I would suggest getting a tooth brush and some warm soapy water and just scrub them off.

To get rid of scale you need to suffocate them. Due to the hard shell they are resistant to taking in most insecticides. Buy or make a oil based insecticide and apply to the entire plant. The oil sticks to the scale and suffocates them. White or neem oil work well.

There is a product called pst oil that works and does not used a harsh chem, ror you can go for a product called anti scale that is white oil + Malathion. The anti scale will kill them off pretty quick the brown and the white.

Look around your pots and see if you have ants. Ants enable scale to spread quickly. n most cases if you have ants you have scale. The ants eat the sweet residue left by the scale.

Cheers HN ,
yeah i thought of just scrubbing them off but it is a crest and i want to keep it as clean as possible.
Thanks for the chem advice, i'll check out my local nursery and bunnings asap. should i keep the plant shaded while it is being treated with the oil based insecticide? i don't want to burn it...on the upside, gymnos love the shade lol.

Hey Lewis I use Rogor as a spray and that gets rid of them some times it takes a couple of doses.

I used white oil once on cactus and I hated it.............left an oil film on the plant for months, but that was years ago and have not used it since.

If you use an oil keep the plant in the shade.........

Update: scale dead
white oil did it.
Thanks mates.
yes Betty i put it in the shade... fortunately it's a Gymnocalycium and thrives in those conditions.

will it need to stay in the shade until the oil washes off? in a couple of months?

Good to hear you beat them lewis. Scale are not a huge problem to cacti, only drama is when there are thousands of the buggers.

watertrade wrote:

will it need to stay in the shade until the oil washes off? in a couple of months?

I think it would depend on SP. Cereoids sp are fine in the sun. Once the scale is dead you could wash the oil off with a weak soapy water solution.

well its a small gymno and they burn easily enough without oil on them in the sun so im thinking ill keep it in the shade for safety

Yeah.. i'll try washing off the oil soon. it does appear to have left a film on the plant..