Why We Rebuilt From Scratch
The original SoilIQ was built fast. It was a native shell wrapping a web app — React, Recharts, a bundle of JavaScript that ran inside a browser view. It worked. People used it. It got real growers real data. But it was always a compromise: slow launches, no widgets, no Watch app, no offline mode, no haptics, no platform-native feel. Every new feature fought the architecture.
SoilIQ 2.0 is what happens when you stop compromising. Every screen, every animation, every chart, every data model was written in Swift and SwiftUI. No web views, no bundlers, no JavaScript runtimes. The app launches in under a second, runs completely offline from cached data, and feels like it belongs on iOS — because now it actually does.
The soil intelligence behind the app didn't change — the same four-depth model, ERA5-Land integration, precipitation cooling, NWP artifact correction, and ISRIC SoilGrids texture data that powered v1. But now all of it is wrapped in an app that can also live on your wrist, your lock screen, and your home screen simultaneously.
Here's everything that's new.
PlantAI: 133-Crop Plant Intelligence
The biggest new feature in SoilIQ 2.0 is PlantAI — a planting readiness engine that evaluates 133 crops across 13 categories against your current soil conditions and classifies each one into one of four buckets.
Four buckets. 133 crops. Zero calendar math.
Ready Now, This Week, Coming Up, and Not Yet — each crop sorted by how close the current soil temperature is to its optimal planting range. PlantAI knows each crop's minimum germination temperature, optimal range, and GDD requirements. It checks the forecast, not just today.
Each crop in the database has a minimum soil temperature for germination, an optimal range for fastest emergence, the soil depth most agronomically relevant to that crop, and the growing degree days needed to reach maturity. PlantAI evaluates all of these simultaneously against your current readings and the 14-day forecast.
The 13 crop categories span vegetables, root crops, herbs, cool-season grasses, warm-season grasses, legumes, alliums, brassicas, cucurbits, nightshades, grains, cover crops, and fruit. Whether you're seeding a lawn, planting a raised bed, or starting transplants — PlantAI covers it.
PlantAI uses the soil depth that matters for each crop. Surface temperature for germinating fine grass seed. 2-inch depth for small vegetables. 6-inch depth for transplants and warm-season crops. The right depth for each decision, automatically.
14-Day Soil Temperature Forecast
SoilIQ v1 showed you where you stood. SoilIQ 2.0 shows you where you're going. The new forecast tab gives you 14 days of soil temperature at all four depths, plus a full-year view and an interactive heatmap.
Stop guessing. See the next two weeks of soil.
The 14-day list shows daily soil temperature at your selected depth alongside air temp range and frost flags. The heatmap view shows all four depths side-by-side so you can see how temperature moves through the soil profile over time. A full-year chart shows the seasonal arc.
Forecast data comes from Open-Meteo's NWP blend — short-range high-resolution model for the first 7 days, medium-range ensemble for days 8–14. SoilIQ applies its NWP artifact correction to smooth over the model boundary transition and produce a physically continuous forecast curve.
Three-Tier Frost Alerts
Previous versions of SoilIQ flagged frost nights with a single warning. SoilIQ 2.0 now distinguishes between three meaningfully different frost events — because a 31°F night is not the same as a 20°F night, and your response shouldn't be either.
Not all frost is the same.
Light frost (28–36°F) will burn tender annuals. Hard freeze (20–28°F) damages established plants. Killing freeze (below 20°F) destroys almost everything unprotected. Each tier has its own color, action message, and push notification — so you know exactly what to do before it happens.
Frost tiers appear as colored dots on the 7-day sparkline on the Today tab — larger dots for more severe events, with glowing halos for hard and killing freeze nights. Scrub the sparkline with your finger to see the tier name inline. The forecast tab shows the worst tier in the visible window as a summary chip.
Push notifications use tier-specific language. A killing freeze tonight gets a different alert than a light frost next Thursday — because they require different responses, and a single generic frost warning trains people to ignore it.
Apple Watch App
SoilIQ 2.0 ships with a native Apple Watch companion. Glance at your wrist to see current soil temperature at your selected depth, soil conditions, and moisture level — without touching your phone.
Warming trend
Your soil data. On your wrist.
The Watch app shows current soil temperature at your selected depth, a conditions summary, and a moisture reading. It stays in sync with your iPhone via WatchConnectivity — the same data, no extra API calls. Complications support is built in, so you can add soil temperature to any watch face.
The Watch app uses Apple's WatchConnectivity framework to receive data from the iPhone app, so it never makes its own network requests. Your watch data is always in sync with what the phone last fetched — no duplicate API usage, no battery drain on the watch side.
Live Activity & Home Screen Widgets
SoilIQ 2.0 puts your soil data everywhere iOS lets you put it: the Dynamic Island, the lock screen, and the home screen.
Live Activity. Dynamic Island. Three widget sizes.
Enable the Live Activity in Settings and your current soil temperature shows on the lock screen and in the Dynamic Island in real time. Home screen widgets in small, medium, and large sizes — the large widget includes a 5-day forecast bar chart. All widgets refresh immediately when the app fetches new data.
iPad & Universal Layout
SoilIQ 2.0 is a universal app. On iPhone it's a tab bar. On iPad it automatically adapts to a sidebar layout — all four tabs become a persistent sidebar navigation with a "🌱 SoilIQ" header and full-width content views optimized for the larger canvas.
All main views — Today, Forecast, PlantAI, and Journal — are centered at a comfortable reading width (720pt) on iPad while backgrounds stay full-bleed. If you're managing a large property and prefer working on a tablet, the app is built for it.
Soil Journal
The Soil Journal lets you log observations alongside automatically captured soil temperature data. Every entry records the current soil conditions at the moment you write — temperature at all four depths, moisture, and conditions — so you can go back and see exactly what the soil was doing when you planted your first tomatoes of the season or noticed stunted germination.
Entries support up to 4 photos from your library (resized and compressed automatically), free-form notes, and mood tags. When you have at least two entries with soil temperature readings, the journal shows a sparkline chart of soil temperature progression across your entries — your own personal soil history, built automatically as you go.
Probe Calibration
No model is perfect for every garden. Your specific microclimate — mulch cover, shade, irrigation patterns, soil amendments — can push your actual soil temperature away from what the NWP model predicts. Probe Calibration lets you close that gap permanently.
Take a reading with a physical soil thermometer at any of the four depths, enter it in SoilIQ, and the app computes and stores the offset. From that point forward, every temperature display, every PlantAI recommendation, and every action insight uses your calibrated value — not the raw model output. The offset is applied at render time, not baked into the data, so you can update or clear it any time without losing your history.
Why this matters: A 4°F systematic offset between your soil and the model isn't unusual — raised beds, dark mulch, south-facing slopes, and clay-heavy soils all shift the reading. One calibration step and SoilIQ knows your actual garden, not the grid average.
Everything Else in 2.0
Interactive Hourly Charts
Scrub through today's hourly soil temperature curve. A crosshair + callout shows the exact temperature at any hour.
Soil Health Score
A 0–100 composite score synthesizing temperature alignment, forecast trajectory, historical percentile, moisture, and precipitation stress.
Growing Degree Days
GDD accumulation tracked per-crop using the correct base temperature for each species. Fahrenheit conversion uses proper delta math (×9/5, not +32).
Saved Locations (Pro)
Save unlimited locations and switch between them instantly. Free tier includes one saved location. Pro unlocks unlimited, with 7-day subscription trial.
Full Offline Mode
All cached data loads instantly with no network connection. The app degrades gracefully — no spinner of doom, just your last known data with a timestamp.
Background Refresh
BGAppRefresh keeps data current overnight. The app fetches on a schedule so the widget and Watch app always show fresh data, even if you haven't opened it.
Get SoilIQ 2.0
SoilIQ 2.0 is a free update for existing users and a free download for anyone new. The core app — four-depth soil temperature, 14-day forecast, PlantAI, frost alerts, Watch app, widgets, and Live Activity — is completely free. SoilIQ Pro ($4.99/month or $29.99/year, with a free 7-day trial) unlocks unlimited saved locations.
If you've been following the development of v2.0, this is what we were building toward. If you're new here: welcome. Your soil data is waiting.
SoilIQ 2.0 — Free on iPhone, iPad & Apple Watch
Four soil depths, 14-day forecast, 133-crop PlantAI, three-tier frost alerts, Live Activity, home screen widgets, and native Apple Watch support. No subscription required for core features.