Introduction
Whether you're managing agricultural boundaries or preparing data for upload to platforms like the Meridia Verify Portal, making sure your spatial data is accurate and clean is essential.
In this guide, we’ll walk you through how to edit farm plot polygons in QGIS, focusing on reshaping features and aligning them neatly with surrounding elements, such as roads or field edges. This process is also aided by the Snap feature in QGIS, which helps in editing your data while maintaining the relationship between the data.
By the end, you'll have the confidence to tidy up your plots, avoid topological errors, and produce GIS data that’s ready for analysis or submission.
Getting Started: What You’ll Need
Before diving in, make sure you’ve loaded your farm plot polygon layer into QGIS.
Step 1: Enable Editing Mode
To begin editing, you’ll need to put the layer into editing mode:
Right-click the Farm Plot layer in the Layers Panel
Choose Toggle Editing.
When editing is active, you’ll see a small pencil icon next to the layer name.
Step 2: Ensure the Right Toolbars Are Enabled
To access all the necessary tools, make sure the following toolbars are turned on:
Right-click in any empty space on the QGIS toolbar area.
Tick the following:
Shape Digitising Toolbar
Digitising Toolbar
Advanced Digitising Toolbar (optional)
Snapping Toolbar (essential for alignment)
Step 3: Edit the Polygon with the Vertex Tool
The Vertex Tool is your main instrument for reshaping polygons by adjusting their corners (vertices):
Select it from the Digitising Toolbar.
Click on the farm plot polygon to reveal its vertices (small square points).
You can then:
Add a new vertex: Hover along an edge until a ‘+’ symbol appears, then click to insert a new point.
Move a vertex: Click and drag any existing point to reshape the boundary.
📄Case Example: Suppose your farm plot boundary extends too far into an uncultivated area, or doesn’t quite follow a nearby road or natural feature. You can:
Drag vertices inward to cut out unwanted sections.
Add new ones to better trace visible features on your basemap, such as roads or footpaths, by activating the Snapping Tool in your toolbar.
This manual editing process helps ensure the farm plot matches the actual land use on the ground. Editing your farm plot polygons with precision leads to meaningful results:
Better Data Quality – Accurate boundaries support better spatial analysis.
Platform Compliance –Systems like Meridia Verify often require clean, topologically valid data before allowing uploads.
Informed Planning – Accurate maps improve decisions in farm planning, land management, and yield tracking.
Step 4: Additional Tools (Optional)
Beyond the Vertex Tool, QGIS offers a few more editing tools worth exploring:
Move Feature Tool – Relocates the entire farm plot;
Rotate Feature Tool – Rotates the plot to better fit the context;
Scale Feature Tool – Adjusts the overall size of the polygon, and many more.
These other tools are especially handy if your farm plot needs a broader realignment.
📌Editing Tips and Best Practices
Save Often – Click the Save Layer Edits button (floppy disk icon) regularly to avoid losing your progress.
Snapping Settings – Configure snapping tolerance carefully so that vertices lock into place without drifting onto the wrong feature. Use snapping modes like vertex, segment, or area, depending on what you're aligning with.
Summary
This tutorial has walked you through the essential steps for editing farm plot polygons in QGIS. By using tools like the Vertex Tool and snapping settings effectively, you’ll ensure your spatial data is tidy, precise, and ready for whatever comes next, whether it’s analysis, reporting, or uploading to a verification platform.
Thanks for following along, and happy mapping!