I don't know. So I did a little googling:
Control Strategies
Early detection of spider mites, before damage is noticed, is important. The tiny spider mites can be detected by taking a piece of white paper or cardboard and striking some plant foliage on it. The mites can be seen walking slowly on the paper. If 10 or more mites per sample are common, controls may be needed.
Option 1: Cultural Control - Syringing Since rainy weather seems to knock off spider mites, using a forceful jet of water from a hose (syringing) can perform the same task. A regular syringing can keep spider mites under control on most ornamental plants in the landscape. This technique also helps conserve natural predators.
Option 2: Cultural Control - Quarantine and Inspection The twospotted spider mite is often introduced on infested bedding and house plants. When purchasing new plants, carefully inspect the lower leaf surface for any signs of mite activity. New house plants should be quarantined from other plants until you are sure that no mites are present.
Option 3: Biological Control - Predators There are numerous insects (lacewings and lady beetles) that prey on spider mites. However, the most commonly sold predators are other types of mites. Predatory mites (usually Phytoseiulus spp., Amblyseius spp. or Metaseiulus spp.) can be purchased and released onto infested plants. Be sure to check listings to determine which species is appropriate. Some species are host specific and each predator works better under different weather conditions. If predators are used, do not apply pesticides that will kill them.
Option 4: Chemical Control - "Soft Pesticides" Most spider mites can be controlled with insecticidal oils and soaps. The oils, both horticultural oil and dormant oil, can be used. Horticultural oils can be used on perennial and woody ornamentals during the summer at the 1 to 2 percent rate. Higher rates of horticultural oil (3 to 4 percent) or dormant oil are useful for killing mite eggs and dormant adults in the fall and spring. The insecticidal soaps are useful in the warm season. Remember that mites are very tiny and soaps and oils work by contact only. Therefore, thorough coverage of the plant is necessary for good control.
Option 5: Chemical Control - Miticides Spider mites are usually not killed by regular insecticides, so be sure to check the pesticide label to see if "miticide" is present. Pesticides claiming "for mite suppression" are usually weak miticides and will not perform well. There are few products available to the homeowner. Dicofol (=Kelthane) is registered for over-the-counter use but is difficult to find. Acephate (=Orthene), dimethoate (=Cygon), chlorpyrifos (=Dursban), diazinon, disulfoton (=Di-syston), and malathion have over-the-counter product labels but are considered weak miticides.
Avermectin (=Avid), bifenthrin (=Talstar), dienochlor (=Pentac), fenbutatin-oxide (=Vendex), fluvalinate (=Mavrik), oxamyl (=Vydate), oxydemeton-methyl (Metasystox-R), oxythioquinox (Morestan), and propargite (=Omite) are restricted use pesticides available only to licensed applicators.
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http://http://www.google.com/url?sa=t&source=web&cd=1&ved=0CB8QFjAA&url=http%3A%2F%2Fwww.getridofthings.com%2Fget-rid-of-spider-mites.htm&ei=SLGxTZL4I8nY0QG1n6XXCQ&usg=AFQjCNFoLxFTBPJEQPto4jDtJQRgANy3lw
http://http://www.google.com/url?sa=t&source=web&cd=3&ved=0CC8QFjAC&url=http%3A%2F%2Fwww.cannabisculture.com%2Fv2%2Farticles%2F3109.html&ei=SLGxTZL4I8nY0QG1n6XXCQ&usg=AFQjCNGnRDn2rj4CouH9wIfqyjCNcj3feQ
In that last link I see Neem Oil listed. Neem is a very good compound for CP's, in general, and aphids, specifically. Neem can be purchased at places like Lowes. I use it to eliminate aphids.