SAFETY WARNING
If you have any current medical condition(s) or any unknown/undiagnosed conditions that might be affected by plants we recommend you avoid contact with them. Please click here for additional guidance.

Where to make electrical connections

A basic measurement can be done by making electrical connections to main stem and branch. Then moniting for electrical signals over time.
How to make electrical connections to plants
There are several methods with different advantages & disadvantages. For example, using a ‘weak’ crocodile clips and soft aluminum tape liner can do minimal damage to the plant but poor connection. Conversely, inserting a needle electrode provides a secure connection but damages the plant.
Another factor to consider is the ‘hardness’ of the plant’s stem/branch. Obviously, a needle electrode is much easier to insert into soft rather than woody stem. Therefore, homemade needle electrodes are better suited to larger plants with soft stems. They can be made from blunt stainless steel darning needles which are (relatively) chemically inert.
Electrical activity in the ‘middle’ of the stem/branch can be different to electrical activity on the surface of steam/branch. So the type of electrode will affect what is recorded.
Veterinary electrode clip
If you want to record measurements at numerous locations with minimal damaging to plant you can purchase reusable veterinary electrode clip which are used for EKG/ECG. Some are silver coating for better conductivity and corrosion resistance, see below:
Veterinary electrode clip are available online from several suppliers, for example Amazon.

Enshey

Suppliers of needle electrodes
Needle electrodes (with twisted cables) are available from medical suppliers but should only be used by experienced & competent users due to risk of needle-stick injury.

GVB-geliMED (Germany)

unimed (UK)

Plant recordings with different electrodes

Click here for example recordings of plants via different types of electrodes