Electricity
Plants sense the electrical environment, and themselves use electricity as a communication conduit. For instance, Venus flytraps snap shut based upon electrical messages from triggered hairs.
Clouds carrying rain pronounce their arrival with electrical fanfare. As rain droplets grow they build up large negative charges. To take full advantage of rainfall, a complex cascade of enzymatic actions within plants take place in preparation. Dried leaves reactivate metabolism, getting ready to receive the water to come.
Flowers are a multifarious advertisement. Besides their good looks, scents, and feel, flowers emit electric fields which beckon.
In foraging afield, bees build a positive charge from flapping their wings. This charge helps pollen stick to them.
Alighting upon a flower affects its electric field for a time. From this a bee can sense how recently has flower has been serviced by another, and so determine whether the flower is worth the trouble of landing.
