Maximize almond yields

1. How does VWC monitoring specifically assist in Regulated Deficit Irrigation (RDI) during the critical hull split stage?

During hull split, growers intentionally induce mild water stress to promote uniform ripening and reduce Navel Orangeworm (NOW) infestations. VWC sensors allow growers to precisely navigate this “stress window” by ensuring moisture levels stay within the targeted deficit range without crossing into severe stress that could cause premature leaf drop or “stick-tights.”

2. Almonds are highly sensitive to salinity and Boron; how can sensors help manage the “leaching fraction” in these orchards?

By using the Dynamic EC feature alongside multi-depth VWC data, growers can determine exactly when salts have accumulated in the root zone. This allows for a targeted “leaching event” where just enough water is applied to push salts below the 36-inch root zone, preventing toxic salt buildup while minimizing water waste.

3. Mature almond trees can have roots extending beyond 4 feet; why is monitoring at the 36-inch (90cm) depth crucial for these orchards?

While the majority of active “feeder” roots are in the top 2 feet, the 36-inch sensor acts as a “sentinel” for deep percolation. If VWC increases at this depth during standard irrigation, it indicates that water (and expensive Nitrogen) is moving past the primary root mass and being lost to the subsoil.

4. How should a grower correlate VWC sensor data with manual Stem Water Potential (SWP) “Pressure Bomb” readings?

VWC provides continuous data on *how much* water is in the soil, while SWP measures the *tree’s response*. By “pairing” these readings for one season, a grower can establish a VWC stress threshold. Once this baseline is set, the grower can rely on the real-time sensors to know when the tree is reaching its stress limit without needing to manually pump pressure bombs daily.

5. Why is moisture monitoring during the post-harvest period often considered as important as the pre-harvest period for almonds?

Post-harvest is when bud differentiation occurs for the following year’s crop. Severe moisture stress during this period can drastically reduce the number and quality of flowers in the next spring. VWC sensors ensure the orchard recovers from the harvest-induced “dry down” quickly enough to support next year’s yield potential.

6. Almonds are heavy users of Nitrogen; how does soil moisture precision impact the nitrogen use efficiency (NUE)?

Nitrogen is highly mobile in water. Precision monitoring ensures that fertigation events only saturate the soil to Field Capacity within the root zone. This keeps the nitrogen “locked” in the upper soil layers where the tree can absorb it, preventing it from leaching into the groundwater and ensuring compliance with California’s Irrigated Lands Regulatory Program (ILRP).

7. Can soil moisture sensors play a role in almond frost protection strategies during early spring bloom?

Yes. Moist soil absorbs more solar radiation during the day and releases more heat at night than dry soil. Growers use VWC data to ensure the orchard floor is at Field Capacity leading up to a frost event, which can keep the orchard 1–2 degrees warmer—often the difference between a successful crop and a total loss.

8. Most almond orchards use micro-sprinklers; how does this affect where a Sensoterra sensor should be installed compared to a drip-irrigated field?

In micro-sprinkler systems, the sensor should be placed mid-way between the sprinkler head and the tree trunk. This area represents the “average” moisture of the wetted pattern. Placing it too close to the head will result in false “over-wet” readings, while placing it at the edge of the throw will show “dry” readings that don’t reflect the main root zone.

9. How do different almond rootstocks (e.g., Nemaguard vs. Hansen 536) influence the VWC thresholds a grower should set?

Peach-Almond hybrids like Hansen 536 are often more vigorous and can have higher water demands than standard Nemaguard rootstocks. Growers must set their VWC “refill points” slightly higher for these high-vigor rootstocks to prevent the rapid depletion of available water that can occur during a Central Valley heatwave.

10. Sensoterra sensors measure soil temperature; how is this data used during the “wake up” period in February/March?

Root activity in almonds generally begins when soil temperatures reach approximately 55°F (13°C). Monitoring soil temperature allows growers to time their first “irrigation/fertigation” of the season perfectly—ensuring that nutrients are applied only when the roots are actually active and able to take them up.