February PTCA Meeting: Soil Science & Irrigation w/ Juerg Spoerri
We are pleased to welcome Juerg Spoerri as our February guest speaker at Jimmy’s of Santee. Juerg is the owner of Agrowinn Fertilizers, a Southern California–based company that manufactures and supplies organic fertilizers and soil amendments for use in arboriculture, landscape maintenance, agriculture, and home gardening.
Juerg has spent decades working directly with soils, developing products and approaches focused on improving soil structure, nutrient cycling, and biological activity. His work emphasizes the idea that plant health begins below ground, and that long-term success depends on understanding how soil chemistry, biology, and management practices interact over time. Agrowinn products are widely used throughout the region and are approved for organic applications, making them a familiar resource for many professionals in the field.
Following January’s presentation by Lee Wozniak on fertilizers as pesticides, Juerg’s talk provides a timely and complementary perspective. While Lee focused on how fertilizers can influence pest pressure and plant defense, Juerg will expand the conversation to the role of soil health in supporting resilient trees and landscapes. His presentation is expected to touch on practical, real-world observations from years of manufacturing, testing, and field use of soil amendments across a wide range of site conditions.
Although the specific topic will be shaped by Juerg’s experience and ongoing work, we can expect a thoughtful discussion on how soil-based management strategies affect plant performance, stress tolerance, and overall landscape outcomes. This presentation should be especially relevant for arborists, landscape professionals, and anyone interested in making more informed decisions about soil and nutrient management.
Location: Jimmy’s of Santee
Date: February 3, 2026
Time: : 6:00 PM
Cost: $15 Member who Pre Register, $35 Day of.
Meeting Details
Date: Tuesday, February 3, 2026
Location: Jimmy's of Santee
Time: 5 PM- Board Meeting/6:00 PM Presentation Begins
Cost:
$15 Members if pre-registered- be sure to log in for member benefits!
$35 Non Member/Member Day Of