Bluelab Soil pH Pen – Digital Soil pH and Temperature Meter for Growing Media

The Bluelab Soil pH Pen is a portable digital testing instrument designed to measure pH and temperature directly in the root zone of plants. Suitable for soil, coco coir, potting mixes, and other compatible growing media, this compact meter helps growers monitor root-zone conditions and make informed decisions about nutrient management.

Soil pH plays an important role in determining how effectively plants can absorb nutrients. When the growing medium becomes too acidic or alkaline, essential nutrients may become less available, even when adequate fertilizer is present.

The Bluelab Soil pH Pen provides accurate readings without requiring growers to collect and prepare separate soil samples for every measurement. Its integrated soil dibber helps create an opening for the probe, while the backlit digital display makes results easy to read.

Ideal for indoor gardening, greenhouse production, container growing, and professional horticulture, this waterproof instrument is also suitable for testing compatible nutrient solutions.

Accurate pH and Temperature Measurements in the Root Zone

The Bluelab Soil pH Pen measures two important growing parameters:

Soil and Growing Media pH

The meter measures pH on a scale from 0.0 to 14.0, allowing growers to identify acidic, neutral, or alkaline root-zone conditions.

Monitoring pH helps growers determine whether their soil or substrate is within the preferred range for their crops. The appropriate pH depends on the plant species, growing medium, and nutrient management program.

Root-Zone Temperature

The integrated temperature sensor measures from 0 to 50°C (32 to 122°F), providing useful information about conditions surrounding plant roots.

Temperature readings can help growers identify environmental changes that may affect root activity and nutrient uptake.

The meter also includes automatic temperature compensation to support consistent pH measurements across its specified operating range.

Key Features and Benefits

• Direct Soil pH Testing: Measures pH in compatible soils and growing media without requiring routine preparation of a separate soil-water sample.

• Temperature Measurement: Displays root-zone temperature in Celsius or Fahrenheit.

• Accurate Digital Readings: Provides pH resolution of 0.1 and accuracy of ±0.1 pH at 25°C.

• Integrated Soil Dibber: The protective cap doubles as a tool for making a hole before inserting the probe.

• Backlit LCD Display: Makes measurements easy to read in greenhouses, grow rooms, and other working environments.

• Waterproof Construction: Designed to withstand regular use in wet growing environments.

• Hold Reading Function: Allows users to temporarily retain a measurement on the display.

• Automatic Power-Off: Helps conserve battery life when the instrument is not in use.

• Two-Point pH Calibration: Supports calibration using pH 7.0 and pH 4.0 solutions.

• Portable Design: Convenient for checking multiple containers, garden beds, and growing areas.

• Versatile Applications: Suitable for soil, coco coir, potting mixes, and compatible nutrient solutions.

How to Use the Bluelab Soil pH Pen

The Bluelab Soil pH Pen is designed for direct measurements in moist growing media.

Step 1 – Calibrate the Meter

Before its first use, calibrate the instrument using fresh pH 7.0 and pH 4.0 calibration solutions, following Bluelab's instructions.

Step 2 – Prepare the Growing Medium

Choose a representative location near the plant's root zone. The medium should have sufficient moisture to make reliable contact with the probe.

Use the integrated soil dibber to create a suitable opening in the growing medium.

Step 3 – Insert the Probe

Remove the protective cap and gently insert the probe into the prepared opening. Avoid applying sideways pressure or forcing the probe into compacted material.

Step 4 – Read the Measurements

Allow the display to stabilize before recording the pH and temperature readings.

For larger beds or growing areas, take measurements from several locations to obtain a more representative assessment.

Step 5 – Clean and Store

After each use, rinse the probe with clean water and replace the protective cap containing the appropriate KCl storage solution.

Important: Never use the sensitive pH probe itself to create holes in soil. Always use the supplied dibber to prevent damage.

Technical Specifications

What's Included?

The standard Bluelab Soil pH Pen package includes:

• 1 × Bluelab Soil pH Pen
• 1 × Integrated protective storage cap and soil dibber
• 1 × 18 mL pH 7.0 calibration solution sachet
• 1 × 18 mL pH 4.0 calibration solution sachet
• 1 × Bluelab KCl probe storage solution sachet

The pen operates using a single AAA alkaline battery.

Maintenance and Calibration

Regular maintenance is essential for obtaining reliable measurements and protecting the instrument's sensitive pH probe.

Bluelab recommends cleaning and calibrating the Soil pH Pen at least once per month and after probe cleaning.

Use fresh pH 7.0 and pH 4.0 calibration solutions for two-point calibration. After testing, rinse away soil particles and residues to prevent contamination.

The probe must remain hydrated during storage. If it accidentally dries out, Bluelab recommends soaking it in KCl storage solution for approximately 24 hours before attempting calibration.

Proper handling and storage help extend the useful life of the instrument and maintain measurement accuracy.

Why Choose the Bluelab Soil pH Pen?

The Bluelab Soil pH Pen offers a practical way to monitor the growing medium directly, rather than relying only on the pH of irrigation water or nutrient solutions.

This distinction is particularly important in soil and coco-based cultivation, where the pH surrounding plant roots can differ from the water entering the container.

Its portable construction, easy-to-read display, and integrated dibber make regular testing convenient across multiple plants and growing areas.

For growers seeking a digital soil pH meter in Canada, the Bluelab Soil pH Pen combines precise measurements with straightforward operation and maintenance.

Frequently Asked Questions About the Bluelab Soil pH Pen

What does the Bluelab Soil pH Pen measure?

The Bluelab Soil pH Pen measures pH and temperature directly in compatible soils and growing media. It can also be used in suitable nutrient solutions.

Can the Bluelab Soil pH Pen be used in coco coir?

Yes. The meter can be used in moist coco coir and other compatible growing substrates. Prepare an opening with the supplied dibber and ensure the probe makes proper contact with the medium.

Does the Bluelab Soil pH Pen measure EC or nutrient concentration?

No. The Soil pH Pen measures pH and temperature, not electrical conductivity or nutrient concentration. A separate EC meter is required for those measurements.

Can it measure pH directly in soil?

Yes. The integrated soil dibber allows users to prepare an opening for direct root-zone measurements without requiring a separate slurry test for routine checks.

How often should the Soil pH Pen be calibrated?

Bluelab recommends calibration before first use, after cleaning, and at least once per month. Always follow the manufacturer's calibration instructions.

Can the Soil pH Pen be used in nutrient solutions?

Yes. The instrument can measure pH and temperature in compatible nutrient solutions with sufficient electrical conductivity. Bluelab specifies a minimum of 0.2 EC for solution measurements.

What is the difference between the Bluelab Soil pH Pen and the regular Bluelab pH Pen?

The Soil pH Pen is designed for direct measurements in growing media and includes a soil dibber for safely preparing an opening. The regular Bluelab pH Pen is primarily intended for testing liquid nutrient solutions.

How should the Bluelab Soil pH Pen be stored?

Rinse the probe after use and replace the protective cap with the appropriate KCl storage solution. Never allow the pH probe to dry out, and do not store it in distilled or deionized water.