How to choose crop and plant test instruments
By Grant, Inspection Tool Specialists. Reviewed November 2026.
Three things decide which crop or plant instrument you need: the plant characteristic you must measure (leaf colour, leaf size, water status or gas exchange), whether you test in the field or in a laboratory, and whether the work is for routine management or research. Answer those first.
Which instrument?
| Need | Instrument | Typical in our range |
|---|---|---|
| Leaf colour and nitrogen status | Chlorophyll meter | CM-B portable chlorophyll meter |
| Leaf thickness | Leaf thickness gauge | LTG-1 leaf thickness gauge |
| Leaf area | Leaf area meter | LAM-A portable leaf area meter |
| Plant water potential | Water potential analyser | PWP-II water potential analyser |
| Transpiration and stomatal conductance, research | Gas exchange meter | PTRM-1000 transpiration meter |
Field use and records
Plant measurements vary through the day and with the weather, so take readings at the same time of day, on comparable leaves, and record the conditions. For research, agree the protocol before you start, so readings across seasons or sites can be compared.
Price guide
As a guide to our current range, including VAT: leaf thickness gauges from about R5,100; chlorophyll meters from about R17,400; leaf area meters from about R30,400; water potential analysers from about R162,800; gas exchange meters from about R103,200. Prices change, so check the product pages and confirm the sensors and software each quote includes.
Questions we will ask you
Tell us the crops or plants, the characteristic you must measure, whether you test in the field or laboratory, whether the work is routine management or research, the protocol you follow, and the records you must keep. With that we can recommend an instrument and provide pricing.