Growing the Valley
Science & Ideas
About
This is a podcast that goes over new research and basic information about growing orchard crops in the Central Valley of California
Episodes
- ACC research in olives with Becky Wheeler-Dykes
Becky Wheeler-Dykes, an advisor, shares preliminary findings on ACC research for fruit removal in table olive production. The research, conducted with UC Davis, examines ACC's potential efficacy in olives, though the commercial product is…
- Distribution uniformity return on investment tool
Inge Bisconer and Parry Klassen discuss a tool developed with a grant from CURES to help estimate the return on investment for fixing irrigation systems. The episode covers why distribution uniformity tests are important and how the tool a…
- 2026 Prune Fruit Set, GDH30, and Cost of Thinning
In 2026, the Sacramento Valley prune industry faces challenges with high fruit sets, GDH30, and increased thinning costs due to fuel prices. UCCE experts Jaime Ott, Domena Agyeman, and Franz Niederholzer offer crop management insights for…
- Last update from the 3rd generation Regional Almond Variety Trial
The 3rd Generation Regional Almond Variety Trial (RAVT) has concluded, with hosts Luke, Phoebe, and Roger discussing its findings. They cover the overall results and the specific strengths and weaknesses of the 13 varieties that remained.
- The effect of pollen on pistachio fruit and polyphenol deposition
Giulia Marino presents research on the impact of pollen source on polyphenol deposition in pistachios, alongside other findings related to 'pistachio xenia.' The study was conducted with Pat J Brown from UC Davis.
- 2026: Earlier Almond Irrigation Start Revisited
Dr. Or Sperling and Zac Ellis review the 2025 findings from a proactive irrigation scheduling application used in California almond orchards. The discussion includes contact information for the researchers and details about various upcomin…
- Encore: Earlier Irrigation Start in Almond
Drs. Or Sperling and Maciej Zwieniecki discuss their research on almond irrigation, which led to an irrigation scheduling application. The episode also covers almond production in Israel and references the UC Davis Carbohydrate Observatory.
- Polyphenol deposition in pistachios - what is it, and how do cultivar and irrigation influence it?
Polyphenol deposition, or internal kernel discoloration, is a harmless pistachio trait appearing as dark coloration on cotyledons. Researchers Georgia Drakakaki, Phoebe Gordon, and Minmin Wang share initial findings on this phenomenon, inv…
- Encore: Climate Change Part 4: Weeds with Lynn Sosnoskie
This episode of Growing the Valley features Lynn Sosnoskie discussing how climate change may affect weed management strategies in agriculture. The discussion builds on concerns about climate change impacts beyond crop performance, focusing…
- The benefits of applying almond hulls and shells as mulch in orchards
This episode of Growing the Valley features Ellie Andrews examining the benefits of using almond hulls and shells as mulch in orchards. The discussion covers their potential as potassium fertilizer and their impact on soil health.
- Red Leaf Blotch (2026)
The podcast episode addresses Red Leaf Blotch, a new invasive disease in California almond production. It emphasizes early, preventive management with a recommended three-spray fungicide program timed around petal fall and considers cultur…
- Boron fertilization of olives
Elizabeth Fichtner discusses the benefits of boron fertilization for olives and provides guidance on managing boron in olive orchards. The episode is indexed from public RSS feeds.
- Pistachio hull split - how does it happen and why does it change across years?
Shuxiao Zhang and Georgia Drakakaki researched pistachio hull degradation, identifying the processes involved and how in-field conditions influence hull split across different years. Their work clarifies changes in hull integrity that prot…
- Encore: Leslie Holland on Botryosphaeria in Almonds
Leslie Holland details research on fungicides to combat Botryosphaeria infections in almond trees, highlighting the importance of preventative measures in orchard management.
- Pistachio pollination biology and artificial pollination
Elizabeth Fichtner explains pistachio pollination biology, its impact on orchard design, and the importance of selecting the right male pollinator. The discussion also covers research into artificial pollination for pistachios, noting its…
- Water use in regenerative and cover cropped orchards
Research from UC Davis by Kosana Suvocarev investigated water usage in regenerative and cover-cropped orchards. The study focused on potential water competition from cover crops, especially those growing post-bloom, and yielded unexpected…
- 2026 Water outlook episode
Phoebe and Sam Sandovol Solis discuss the water outlook for 2026 and methods for maximizing water infiltration. They also touch on groundwater recharge, soil texture, and orchard locations suitable for it.
- Self-Fertile Nonpareil: Sierra Gold (2025)
Reid Robinson, CEO of Sierra Gold Nursery, details the development of FruitionOne™, a self-fertile Nonpareil almond tree. Both Sierra Gold and Burchell Nursery plan to offer these trees to growers starting in 2027.
- Self-Fertile Nonpareil: Burchell (2025)
Tom Burchell, owner of Burchell Nursery, discusses the development and future for Nonpareil SC+, a self-fertile Nonpareil almond variety. Both Sierra Gold Nursery and Burchell Nursery are partnering with biotech firms, with trees expected…
- Walnut Mold (2025)
Dr. Themis Michailides shares updates on walnut mold research, covering its biology and management strategies. The discussion is based on his lab's findings and is intended for general informational purposes.
- In a Water Scarce Future, How Should we Design Almond Orchards?
Franz Niederholzer explores how to design almond orchards for a water-scarce future under SGMA regulations. He discusses a potential test orchard at Nickels Soil Lab with reduced irrigation and different rootstocks, posing the question of…
- Pulling Past Almond Irrigation Lessons Forward at the Nickels Soil Lab
Franz Niederholzer revisits research on almond irrigation, including microirrigation and drought consequences, from the Nickels Soil Lab
- Almond Environmental Bud Failure / Monterey Leafing Failure (2025)
The 2025 almond season saw significant environmental bud failure, impacting leafing in canopies across the Central Valley. Dr. Tom Gradziel from UC Davis explains the complexities of this disorder and the unusual bloom observed.
- Almond Non-Infectious Bud Failure
Tom Gradziel explains non-infectious bud failure (NBF) in almond varieties, its causes, and the significant progress UC researchers and nurseries have made in managing this issue.
- What is regenerative agriculture? With Amelie Gaudin
Amelie Gaudin joins Phoebe Gordon on Growing the Valley to explain regenerative agriculture. The discussion covers practices that qualify as regenerative, distinctions from conventional agriculture, and the underlying science.
- Walnut scale with Elizabeth Fichtner
This episode features Elizabeth Fichtner discussing walnut scale, a pest that can harm walnut trees. Fichtner covers the insect's lifecycle and available control methods. The discussion focuses specifically on walnuts, not almonds.
- Prunes: Fruit Growth through Postharvest
This episode, the second in a two-part series on prune crop phenology, covers summer fruit growth, financial considerations at harvest, and postharvest practices. It includes insights from UCCE Farm Advisors Franz Niederholzer, Jaime Ott,…
- Prunes: From Buds through Fruit Thinning
This episode covers prune crop production, focusing on fruit bud formation through spring thinning. It discusses the impact of weather during bloom and the subsequent 30 days, introduces a calculator for shaker thinning, and highlights the…
- Oak Root Fungus with Roger Duncan (2025)
Roger Duncan, UCCE Advisor Emeritus, discusses findings from an Oak Root Fungus (Armillaria root rot) rootstock trial, highlighting resistant rootstocks as a solution for orchards. The episode also mentions upcoming agricultural extension…
- Warm Season Phytophthora in Almond with Jim Adaskaveg (2025)
Dr. Jim Adaskaveg discusses managing warm season Phytophthora in almond orchards, noting it is no longer solely an early season problem. The episode also references earlier discussions on Phytophthora with Dr. Greg Browne and Dr. Florent T…
- How do pistachio shells split? With Shuxiao Zhang and Georgia Drakakaki
This episode features Shuxiao Zhang and Georgia Drakakaki discussing their study on pistachio shell splitting. They cover the cellular mechanisms involved, the influence of kernel size on splitting, and why certain pistachio varieties exhi…
- Managing Johnsongrass in Orchards with Ryan Hill (2025)
Ryan Hill joins Growing the Valley to discuss integrated year-round management strategies for Johnsongrass, a perennial weed in orchards. The episode highlights resources from UC ANR for weed identification and management, and lists UCCE w…
- New Walnut Rootstocks (2025)
Dr. Pat J. Brown of UC Davis discusses new clonal walnut rootstocks developed by UC and USDA researchers, highlighting K3 for its growth, yield, and low crown gall. Growers interested in trialing these rootstocks can contact Dr. Brown and…
- Leaffooted Plant Bug & Stink Bugs Part 2: Integrated Management (2025)
Three PhD entomologists discuss integrated pest management for leaffooted and stink bugs in California nut crops. This episode focuses on management strategies, following a prior discussion on pest phenology and monitoring. Information is…
- Leaffooted Plant Bug & Stink Bugs Part I: Phenology and Monitoring (2025)
Three entomologists from UC Cooperative Extension discuss the phenology and monitoring of leaffooted and stink bugs in California nut crops. The episode covers trap and lure updates for leaffooted bugs and directs listeners to the UCIPM we…
- Gophers, Ground Squirrels, Voles, Roof Rats, and Deer Mice… Oh My! (2025)
This episode, a compilation of two from 2022 with a 2024/2025 update, features Dr. Roger Baldwin discussing orchard management of pocket gophers, ground squirrels, voles, roof rats, and deer mice. It includes new research on roof rat contr…
- An Earlier Start to Irrigation in Almond (2025)
Drs. Or Sperling and Maciej Zwieniecki discuss their research on almond irrigation, which has led to an irrigation scheduling application. The episode also covers almond production in Israel and references the UC Davis Carbohydrate Observa…
- Tree Destroyer: Cytospora in Prune (2025)
Themis Michailides from UC Davis at Kearney Ag Center provides updates on the biology and management of Cytospora, a significant fungal canker disease affecting prune production in California.
- The effects of wildfire smoke on nut crops
UC Davis researchers Jessica Orozco and Maciej Zwieniecki are investigating how wildfire smoke affects nut crops in California's Central Valley. They are using data from The Carbohydrate Observatory, collected through citizen science, to u…
- Walnut Rest-Breaking Agents with Katherine Jarvis-Shean
Katherine Jarvis-Shean presents research on the effectiveness of rest-breaking agents for walnuts, noting their impact on bud break, yield, and quality, and how efficacy is influenced by chill accumulation.
- Nonstructural carbohydrates, dormancy and bloom of tree nuts
This episode of Growing the Valley discusses nonstructural carbohydrates as energy storage compounds in trees, their relationship to dormancy and bloom, and the function of dormancy breaking agents. Guests Maciej Zwieniecki and Katherine J…
- Tree nut production and water use outside of the United States
This episode of Growing the Valley discusses tree nut production and water use globally. Phoebe talks with experts about almond production in the Iberian Peninsula, pistachio production in Sicily, and pistachio production in Iran and Afgha…
- The Future of Irrigation with Tom Devol (2024)
Tom Devol discusses past, present, and future irrigation advances for California orchard farmers, who face economic and regulatory challenges. The episode covers potential labor and time savings from new irrigation technologies.
- Tree Destroyer: Phellinus in Prunes (2024)
Laurel Hoffman from UC Davis discusses the biology and management of Phellinus heart rot, a disease that impacts the structural integrity of prune trees. The episode provides updates relevant to growers in the Sacramento and San Joaquin Va…
- Encore: Avocado orchard recovery after wildfire with Ben Faber
This 2020 encore episode of Growing the Valley features insights from Ben Faber on avocado orchard recovery after wildfires. It explores the surprising resilience of trees following these events.
- Walnut Freeze: Remaining Vigilant
Clarissa Reyes and Luke Milliron discuss preparation steps for sudden autumn freeze events affecting California walnut growers, referencing recent frost occurrences and orchard conditions.
- Carpophilus truncatus update with Jhalendra Rijal
Jhalendra Rijal discusses research updates and observations on the Carpophilus beetle, which was first found in California a year ago. Information regarding upcoming extension meetings is also provided.
- Almond Variety Trials 10 Years In
Luke Milliron, Phoebe Gordon, and Roger Duncan discuss ten-year almond variety trials planted across the Central Valley. Information on the trial results can be found in the 2023 report and a future West Coast Nut publication.
- Nitrogen uptake of Golden Hills and Lost Hills
This episode discusses the nitrogen uptake dynamics in pistachio trees, particularly the newer Golden Hills and Lost Hills cultivars. Doug Amaral provides an update on nitrogen demand curves, considering the effects of alternate bearing pa…
- The Walnut Variety Trial and the Walnut Improvement Program
Karla Caldera, a CSUC graduate student, details her research at the Chico State University Farm's walnut variety trial. Dr. Pat J. Brown discusses the UC Davis Walnut Improvement Program, which aims to introduce enhanced plant materials to…