How to treat spider mite on cacti? - briefly
Apply a miticide such as «neem oil» or a horticultural oil, spraying the cactus thoroughly every 5–7 days until mites disappear. Maintain low humidity and discard heavily infested pads.
How to treat spider mite on cacti? - in detail
Spider mites are minute arachnids that feed on the sap of cactus tissue, causing stippling, discoloration, and eventual tissue collapse. Early detection relies on visual inspection of the plant’s surface; the presence of fine webbing and tiny moving specks confirms infestation.
The life cycle progresses from egg to larva, then to nymph and adult within 5–14 days, depending on temperature and humidity. Rapid development necessitates prompt intervention to interrupt reproduction.
Cultural measures reduce mite populations. Maintain low indoor humidity (below 50 %) and provide ample airflow, discouraging mite proliferation. Avoid overhead watering that creates a moist microclimate favorable to mites. Remove heavily infested pads or stems and dispose of them away from healthy specimens.
Mechanical control includes washing the cactus with a strong jet of water to dislodge mites and webs. For larger specimens, gently brush the surface with a soft paintbrush or cotton swab dipped in diluted isopropyl alcohol (70 % solution). Repeat the procedure every 3–4 days until no mites are observed.
Chemical options consist of horticultural oil (e.g., neem oil, petroleum‑based dormant oil) applied at a rate of 2 % v/v, covering the entire plant surface while avoiding runoff into the soil. Systemic acaricides containing abamectin may be used according to label instructions, observing the required pre‑harvest interval for edible cacti.
Biological agents provide sustainable control. Predatory mites such as Phytoseiulus persimilis and Neoseiulus californicus consume spider mites and can be released onto the cactus foliage. Ensure the environment remains above 20 °C for optimal predator activity.
Preventive practices include regular monitoring, quarantine of new acquisitions, and periodic application of a light oil spray during the growing season. Maintaining plant vigor through appropriate watering, well‑draining substrate, and balanced fertilization reduces susceptibility to mite damage.
Overall, an integrated approach—combining environmental management, physical removal, targeted chemicals, and biological control—offers the most reliable solution for eliminating spider mite infestations on cacti.