You will need to take care of the eggs too. Any oil will do if sprayed properly. I know HO works if used repetitively a few times at approx. 10 day intervals. Otherwise you will need to use a chemical acaricide combined with HO.

You may want to try to find a way to add humidity around the tree. Mites seem to explode in warm dry conditions, so if you can do the pebble tray with water thing (if the trees are small) and/or mist around the trees frequently, that might help. As another suggestion, I have seen posts where people with indoor and/or overwintering citrus, will spray the trees down every once in awhile in the shower stall or in the tub with a shower fixture (this will depend on how large the tree is). I know 2 winters ago, I was able to concoct a "shower station" for mine by sitting them in a big muck bucket, surrounding them with some plastic sheeting tucked into the muck bucket and held up with some tall plastic garden stakes. I then used a hand-held sprayer attached to my basement stationary tub faucet, to spray the leaves/stems/trunks with warmish water, with the muck bucket being the catch basin. I now have a 3 gallon wheeled tank sprayer that I use just for watering (it has a couple spray attachments), so I could probably do the same with that and not need a faucet for the water.

1/2 hot water, 1/2 isopropyl alcohol, a squirt of Castille soap, 2 tsps neem oil in 2 L container every 6 weeks as a preventative. I also check everyday for mites but I grow indoors so have big reasons too. In 3 years have had only one infestation and that was when I skipped a spray.

I find that they only think that works is regularly spraying the trees. I alternate between just water and HO. I have to keep it up every week or two. Even if I think they're gone, a few months later I find them again. I know MeyerMike has success with Fish Emulsion for pests too. As Nik said, any oil will kill them, but the eggs will keep hatching. In between sprays, I'll use a qtip and wipe the leaves down with diluted rubbing alcohol. Thankfully, I've never had a bad infestation, but I'm paranoid that they are pests constantly operating at a low level, where I can't yet see evidence. Constant vigilance! It doesn't help that I'm always bringing home new houseplants from the nursery.

Everyone is right about the eggs. I'm not killing off the eggs. Alanna's situation is similar to mine - every time I think they are gone, they reappear. I'm going to see if I can spray my plants using a water bottle and wiping down the leaves (unfortunately, I'm limited in my options). Hopefully, this will add some humidity - my apt is hot and dry during the day - which I am sure the spider mites love.

Besides MeyerMike's use of fish emulsion, I came across a few posts from a few years back about MeyerMike's recipe for rosemary oil and dish detergent spray which seemed to work. Has anyone here used it recently with good result? I wish I could try the fish emulsion, but I don't think my neighbors would be happy with the smell.

I'll be placing an Amazon order soon for Neem and HO this week. Hopefully, they will kill the eggs. Any recommendations for products? Or it really doesn't matter which brand or type?

Wow, spider mites are tenacious.

I use the Dyna-Grow neem oil.

I have a few more questions.

I was wondering if it's true that spider mites can develop resistance to certain chemical sprays such as neem-based spray? I read that with insecticidal sprays they don't, but I'm not sure if I'm remembering that correctly. Are there certain solutions I should be mindful not to overuse or use too often continuously? The spider mites are driving me crazy.

I read that insecticidal sprays kill the spider mites, but don't kill the eggs. Does Neem or HO kill eggs? I haven't been able to find any definitive answer to that. From what Nik and silica wrote, I'm assuming HO does kill the eggs, but not entirely sure if that's what they meant.

Thanks again to everyone who posted.

Do you want a zero effort gaurenteed way to kill them?

Hot shot no pest strips

Miscel,

Mites can and do develop resistance towards acaricides that act biochemically on their organism. They can't and don't develop resistance to pesticides which act mechanically (e.g. they suffocate them, dissolve their external membrane cells and/or kill their eggs.). Oily products belong to the second category. HO does exhibit some ovicidal action also. The oils in some so called 'Neem oil' products may be able to act similarly but Neem extract products which rely on the plant toxin azirachtin for their action don't.

Mites are not insects. The use of insecticides against mites is a no-no as most of them exhibit low efficacy towards mites and will kill their insect predators. Acaricides should be used instead if necessary.

Nik - Let me make sure I got this right. Okay, so no to insecticide, but yes to insecticidal soap sprays which may or may not be ovicidal, but kills spider mites on contact. HO products don't cause them to develop resistance and do work as an ovicidal. While Neem cold-pressed oil might be ovicidal, it should be used judiciously due to potential resistance. Avoid Neem extract products as they may be ineffective.

This is what I found on:

http://ipm.ucanr.edu/PMG/PESTNOTES/pn7405.html

If a treatment for mites is necessary, use selective materials,
preferably insecticidal soap or insecticidal oil. Both petroleum-based
horticultural oils and plant-based oils such as neem, canola, or
cottonseed oils are acceptable. There are also a number of plant
extracts formulated as acaricides (a pesticide that kills mites) that
exert an effect on spider mites. These include garlic extract, clove
oil, mint oils, rosemary oil, cinnamon oil and others. Don’t use soaps
or oils on water-stressed plants or when temperatures exceed 90°F. These
materials may injure some plants, so check labels and/or test them out
on a portion of the foliage several days before applying a full
treatment. Oils and soaps must contact mites to kill them, so excellent
coverage, especially on the undersides of leaves, is essential, and
repeat applications may be required.

Does the above sound right? In which case I may buy some essential oils (cinnamon, rosemary, etc.) from my local natural food store as back-up.

In my shopping cart, I have:

Safer Brand 5118 Insect Killing Soap - 16-Ounce Concentrate

Mother Earth Monterey Horticultural Oil

Dyna-Gro DYNEM008 8 Oz Dyna-Gro® Pure Neem Oil (as recommended by petuniafish)

Does this shopping list look okay? I know this is probably overkill, but the spider mites are driving me crazy.

One last question: How long do you have to go without a spider mite infestation before you can declare the infestation over? I think I've gone about 2-3 months between outbreaks, though I attribute that to the fact that I wasn't always vigilant about inspecting my plants for spider mites.

I was looking at the ingredients list for Monterey HO and saw that it's 80% mineral oil. I have mineral oil that I use for my cutting board and wooden spoons and bowls. Can I use this? Or is the mineral food grade oil different from the one used in HO?

Good quality HO's (paraffin based summer oils) are distilled specially to have high volatility. Thus they evaporate quickly from the plant tissue minimising the potential for tissue burn. Your mineral oil has probably been distilled with other uses in mind..

Thanks Nik. I guess I will keep the Monterey HO in my shopping cart.

Although I have found that citrus are quite resilient to oil overdoses, if you decide to use an HO pay attention to the use instructions and particularly to the prevailing temps before applying. High temps combined with high humidity are a no-no for applying oils. HOs should not be used in combination or in near term to sulphur applications.

I've saw the label warnings about high heat and HO applications. I'm hoping to get the HO before the next heat wave which is around the corner. Thank you for the important reminder.

I'm unclear about what you mean about the sulphur applications. What contains sulphur?

mostly sulphur itself... a good preventive fungicide and miticide. I would not recommend it though to be applied on citrus trees with fruit.

I think this is the first time I've heard of sulphur as a solution for spider mites.

You obviously do not live in a wine producing area..

Well, he is zone 6...

since they are potted plants stick them in a closet at night with a no pest strip every other night for a week and be done with it

pip313 - I read up on the no pest strip and it wasn't recommended to use indoors, especially in enclosed spaces without ventilation. You're right, it seems to be pretty effective. I'm in an apt, and I wish I had an empty enough closet or spare room to stick my plants in with the no pest strip. I think the no pest strip might be a good option for non-city dwellers with space to spare or a dedicated building like a greenhouse or shed to use.

nikthegreek - Sadly, no. I wish I was in a wine producing area as they tend to be located in quite beautiful places. But that explains a lot about your sulphur rec.

I did finally get the Neem and HO today. I used the Monterey HO per the instructions and I was a bit surprised. I thought HO would look more like the mineral oil I use for my wooden boards and cutlery, but it looked and smelled and had the consistency of hair bleach. I wonder if it's more toxic than the hair bleach based on the warnings in the instructions. Mixing it with water, the consistency reminded me of watery milk. Again my expectations didn't match reality, because I was expecting it to be oily like a watery olive oil. It was very lightly greasy and it didn't adhere to the leaves as much as I thought it would. Was I supposed to add oil or something else?

You have done right to use it as per the instructions. HO is specially formulated to create a milky emulsion when dissolved in water. You should (if possible) adjust the sprayer nozzle to a fine setting.

I have never met a product designed to protect plants that is good to inhale, eat or wash you hair with.

I’m a city dweller, I used a closet. But if you don’t have one available then you don’t have one available.

you can tell if you’re too exposed, you can start to feel your chest when you breathe. It’s very noticeable.

but god damn do they work, just don’t hang out with the plants for a long time when they are being treated.

nikthegreek - Haha. I guess you've never colored your hair or someone else's. The hair bleach is pretty noxious and I really thought the mineral oil was mistakenly labeled for a second.

pip313 - Wow, props to you. Reading the boards for weed growers, there were many cautions against using the no pest strips inside homes. In my case, really no space and the plants are in the southern-facing window in my hallway. Very tempted though. Perhaps in my next apt, though hopefully the spider mites won't still be an issue then. Out of curiosity, why the hot shot no pest strip every other night for a week instead of continuously every night for a full week? Also, what about the eggs? Do you have to repeat this a week later to kills any newly hatched spider mites?

miscel - How tall are the trees? Is it possible to enclose them in a large plastic trashbag or "contractor" bag and tie it closed with the strip inside? I know when I have "fumigated" (smaller) plants, I try to get them in a big bag, spray, and then tie the bag closed.

Regarding the HO - if you spray plain mineral oil on waxy leaves, it just mostly rolls off, which is not what you want. That's why these products are formulated with emulsifiers to make it easier to mix with water to dilute for spraying and include "spreader-stickers", that will maximize the ability of the product to actually cling to the leaves. There are most likely volatiles in there that helped to create the mixture that will then evaporate off once the product is sprayed and exposed to air, that will leave just (or mainly) the oil on the leaves.

Even the oil is thin enough to be quite volatile, that's why one shouldn't spray when humidity is high.

jenny_in_se_pa - They are more plants than trees. They range from about 2 ft - 4 ft. Your suggestion is pretty novel. I have to keep it mind. Does it matter what color the bag is and should it be kept away from the sunlight?

What you wrote about the HO makes sense. I think I went into this with a completely different set of expectations based on the mineral oil I use for my wooden kitchen products. That's why I was taken aback when I actually saw the HO and then mixed it with water. I will be spraying them for the second week based on nikthegreek's recommended schedule. Hopefully, the HO will finally kill off the spider mites and the eggs.

nikthegreek - Good to know and keep in mind. I may end up testing the heat and humidity, because there's another heat wave which coincides with the next spray schedule. By the time the heat wave passes I will be away so I may have to spray and hope it's okay.

miscel - Yes you should keep them away from the light when doing any type of pest treatment (whether bagged or not) and since you would be doing this indoors, the indoor temps won't heat inside the bag as much as if this were done outside if there is a heatwave coming, but will hopefully keep most of the "fumes" (volatiles) from the product within the bag to help kill the buggies.

I grow year round indoors and have been successful doing preventative treatment every 6 weeks with Neem oil, isopropyl alcohol and Castille soap. But wouldn't you know with summer travel I missed a treatment and argggghhh- spider mites. So far they've only affected the plumeria plants I have in my grow room, but all the citrus is adjacent. Just sprayed everything tonight. I've read this thread carefully for ideas and since the neem oil has been effective in the past going to stay with it, every 7-10 days for awhile. The darn little buggers. I spray the leaves- underside and top, branches and trunk heavily. Will also spray with water in between the neem over the next several days. If anyone has any further suggestions I greatly appreciate. HATE them.

Nancy, I just bought the DynaGro Neem oil, along with Castile soap and clove oil. I just mixed up a batch and will spray tonight, as my trees have an infestation of mites right now Ugh! I’m thinking of adding HO to the mix as well. I was using a neem extract by GardenSafe, but it did not do the job, even with repetitive treatments.

Hi Kelley. I use Dyna Gro Neem oil too. Just curious- do you know if outdoors spider mites have any natural predators?

I think I read that lady bugs eat spider mites.

I think my spider mites may be gone or at least under control, but I could be wrong. So far no sightings in 2 months and 3 rounds of HO spray. I hope to keep up with spraying my plants with water or insecticidal spray on monthly basis as some have suggested. I found the last time I used HO that it seemed more noxious even when
using gloves with the windows open. Perhaps I'm more sensitive?

As an alternative I may try to do a spray using isopropyl alcohol or essential oil and dish soap spray. I also own the Dyna Gro Neem oil for intractable infestations, though I haven't used it.

If you don't mind wearing a mask and doing it outside, consider using abamectin (an acaricide). It just takes one application in the fall and I am good for the whole winter. You won't need more than a couple mL to last a couple years.

-Tom

Update on the Valentine pomelo from Tom. It is planted in ground and is entering its first winter.

My Four winds New Zealand lemonade tree from Pip is entering its second winter outside and in ground

My seed grown Fukushu Kumquat tree from Cory is entering its 3rd year outside in ground.

Steve