Horticalc

Horticalc is a local, open-source fertilizer calculator for horticultural nutrient solutions. It turns fertilizer analyses, water data, batch volume, doses, and RO mixing into elemental, oxide, NPK, dissolved-ion, ion-balance, and EC results. The Solver works backwards from a nutrient target or published formula to calculate doses from the fertilizers you actually have, making it useful for reproducing or adapting solutions with alternative agricultural products.

Quick start

Windows installer (recommended)

1. Download horticalc-vX.Y.Z-windows-setup.exe from the latest release.
2. Run the installer and choose the destination and shortcuts. It installs for the current user without administrator rights.
3. Start Horticalc from the selected Start Menu or desktop shortcut.

Portable Windows

1. Download horticalc-vX.Y.Z-windows.zip from the latest release.
2. Before extracting, right-click the ZIP and open Properties. If Windows shows Unblock under Security, select it and click Apply.
3. Then extract the complete archive to a writable directory and run Horticalc.exe inside it. See startup problems if it was extracted before unblocking.

Linux

1. Download horticalc-vX.Y.Z-linux.tar.gz for x86_64 from the latest release.
2. Extract it to a writable directory.
3. Run ./horticalc from the extracted directory.

To run from source, see Contributing.

First calculation

1. Open Calculator and set the batch volume.
2. Add a fertilizer and enter its dose.
3. Select or enter the water analysis.
4. Choose Calculate and inspect the nutrient and EC results.

The Solver performs the reverse workflow: provide nutrient targets and the fertilizers it may use, then review the proposed doses before applying them.

Screenshots

Calculator

Solver

System requirements and startup help

Windows 10 and 11 require the Microsoft WebView2 Runtime, which is already present on most current systems. If Horticalc reports it missing, install it from Microsoft.

The Linux build requires GTK 3 and WebKitGTK 4.1:

# Ubuntu, Debian, and Linux Mint
sudo apt update && sudo apt install -y libgirepository-1.0-1 gir1.2-webkit2-4.1

# Fedora
sudo dnf install -y webkit2gtk4.1

If a portable Windows copy reports Mark of the Web, Windows' downloaded-file security metadata, delete the freshly extracted application, unblock the original ZIP if the option appears, and extract it again. Horticalc stores startup details in logs/launcher.log.

Documentation

• Using Horticalc
• Command-line interface
• HTTP API
• Solver and EC models · EC
• Data formats
• Architecture
• Contributing · Releases · Security

Data and safety

Bundled fertilizer data and target profiles are point-in-time references, not manufacturer instructions. Check current labels and technical documentation before mixing or dosing a real solution.

License

Horticalc is licensed under GPL-3.0-or-later. See LICENSE.