Bʏ Mᴀʀʏ Mᴡᴇɴᴅᴇ,
Kenya’s avocado sector is confronting an emerging threat that has put growers and agronomists on high alert. The Persea mite (Oligonychus perseae), a notorious pest responsible for significant avocado losses in parts of California, Spain, and Mexico, has now established itself in Kenya’s avocado-growing regions. Experts warn that without swift, coordinated action, this tiny pest could undermine the country’s position as a leading exporter of Hass avocados.
The Persea mite was first detected in Kenya in November 2023 in Nakuru County. At the time, its presence went largely unnoticed among growers unfamiliar with its characteristic feeding damage. By early 2025, however, the pest had spread to other avocado-producing zones, prompting concerns within the industry. Koppert Kenya, a biocontrol solutions provider, raised the alarm in March 2025, describing the mite as a “silent threat” to the industry’s hard-won gains.
Small in size but capable of causing significant damage, the Persea mite feeds on the underside of avocado leaves, creating pale yellow spots that eventually turn brown and necrotic. The damage, though initially subtle, progressively weakens the tree by reducing photosynthesis and triggering leaf drop. When defoliation occurs, the exposed fruits become susceptible to sunburn, leading to further quality losses.
According to Koppert Kenya, if left unmanaged, Persea mite infestations can result in yield reductions of up to 20 percent. This estimate is consistent with outcomes reported in avocado-producing countries where the mite has been a persistent problem for years. What makes the situation particularly troubling for Kenya is the pest’s affinity for the Hass variety, which accounts for the bulk of the country’s avocado exports.
The timing could not be worse for Kenyan producers. The country’s avocado industry is currently undergoing significant expansion. After a drop in production to 562,000 metric tons in 2024 due to prolonged drought, projections for 2025 indicate a rebound to 585,000 metric tons. Planted area is expected to increase by 6%, reaching approximately 34,000 hectares. With the international avocado market increasingly competitive and export standards tightening, any unchecked pest problem could jeopardize Kenya’s market access.
To address the threat, an integrated pest management (IPM) strategy is being urgently promoted. Koppert Kenya is leading trials of Spical Ulti-Mite, a biocontrol product containing the predatory mite Neoseiulus californicus. This natural enemy of the Persea mite has shown promising results in suppressing mite populations in California, Israel, and now in initial Kenyan trials. According to field reports from Nakuru, farms using Spical Ulti-Mite observed a marked reduction in Persea mite numbers without resorting to chemical sprays.
KEPHIS, the country’s plant health authority, has also moved to heighten surveillance and educate farmers on recognizing early signs of infestation. While official circulars on Persea mite management have not yet been published, KEPHIS officers have participated in field trainings and avocado stakeholder meetings, emphasizing the importance of orchard hygiene, routine monitoring, and cautious pesticide use to preserve natural predators.
International research supports the Kenyan strategy. Studies by the University of California’s IPM program recommend weekly scouting during high-risk periods, beginning with leaf inspections on the underside where mites and webbing are typically found. When about half the leaves in a sample show mite presence, timely intervention using predatory mites or selective miticides is advised. Cultural practices such as removing fallen leaves, controlling alternate weed hosts, and maintaining consistent irrigation are also essential for keeping mite populations in check.
Looking ahead, growers are being urged to prepare for a long-term management challenge. Given the Persea mite’s rapid reproduction completing its life cycle in just 10 to 21 days under warm conditions and the difficulty of eradicating established populations, the pest is likely to become a permanent fixture in Kenyan orchards. However, with disciplined IPM programs, growers can limit its damage and preserve both yields and fruit quality.
The emergence of the Persea mite is a reminder of the vulnerabilities that accompany crop expansion and international trade. As Kenya’s avocado industry continues to grow, maintaining rigorous plant health surveillance and embracing sustainable pest control practices will be critical for safeguarding its international reputation and securing the livelihoods of thousands of smallholder farmers.