Greenhouse Palm Pests

[tjwalters]

Before long I'll be moving my fairly large palm collection back into the conservatory for the winter, and I will inevitably develop a spider mite problem. In fact, I’ve already noticed some webbing on a few that have spent the summer inside – Chamaedorea klotzschiana and C. seifrizii. Out of all of my palms, C. tepejilote, Adonidia merrillii and Wallichia disticha seem to suffer the most, but any of the thinner-leaved palms are at risk.

I’ve used Orthene in the past but it seems to have lost its effectiveness. Imidacloprid works great for scale, but not for mites. Not sure mites are even listed on the label as one of the controlled pests. I’ve also tried predatory mites. Those didn’t work out too well. In fact they were a total waste of time, money and effort.

What are the greenhouse folks here using? What do the professionals use to control spider mites on palms? Does anything work to control these destructive critters?

[kahili]

Mites are tough. Miticides works well, and last a month. You could try a horticultural oil or Neem oil-they are cheaper but you need to spray once a wk until they are gone. Maybe soaps work for others here, I have never tried them though.

[JEFF from Trabuco Canyon CA]

Ortho Orthenex Garden Insect and Disease Control works well. If you want a more natural spray I would go with pure Neem oil but you must be consistent with it.

[Rafael]

By the way, what is the best way to prepare the neem oil water solution? How much neem oil/1l?

[JEFF from Trabuco Canyon CA]

Hi Rafael, It depends on the brand. I tend to add a little extra then what the bottle tells me. Do you know what brand you have?

[JEFF from Trabuco Canyon CA]

I have used this one in the past but it is only 70% Neem oil

Now I use this one which is 100% Neem oil, about $10 more money but well worth it.

I am also finding that Neem is working on Aloe mites which can be hard to get rid of.

Hope this helps.

Jeff

[Rafael]

Hi Rafael, It depends on the brand. I tend to add a little extra then what the bottle tells me. Do you know what brand you have?

I have pure neem oil.

[kahili]

read the label-it will tell you the ratio of Neem to water. It should tell you in one gallon of water

[Turtile]

Permethrin also works.

[tjwalters]

Permethrin also works.

Seems to also work on cats, so that's off the list.

[Matt in SD]

I've had good luck with a product called Ortho Max. I did not have good luck at all with Neem oil. It did suppress the mites, but when I was using Neem oil, I had to spray every week or two and this went on for a couple years. The mites always came back. With the Ortho Max I don't even think I've had to spray every year.

The best thing to do though before just going chemical, is to take the plants out of the greenhouse (if you have a shady place and it's summer), spray the undersides of the leaves every couple days, and move plants back into the greenhouse only if they've been mite free for a couple weeks. While the plants are out of the greenhouse, set off a bug bomb (can be pyrethrin based, or something nastier) in the greenhouse to make sure everything is dead in there. It's a bit of work, but this is the only way I've found to actually get rid of a significant mite infestation permanently.

Matt

[Richard Booth]

I have had good results with these predatory mites http://www.nvsuk.org.uk/garden_equipment/pest-weed-control/product.php?pr=851

(Phytoseiulus persimilis). They need high temps to work effectively though, but i have had big problems with RSM and these predators usually deal with them quite well.