A small group of plants in a building in New York City is quietly exchanging information. Botanicalls opens a new channel of communication between plants and humans, in an effort to promote successful inter-species understanding.

Botanicalls allows plants to place phone calls for human help. When a plant on the Botanicalls network needs water, it can call a person and ask for exactly what it needs. When people phone the plants, the plants orient callers to their habits and characteristics.
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A soil moisture sensor in each plant sends information to an Arduino board which then passes the information to a ZigBee network. An XPort is used to send data via PHP to a mySQL database and to Asterisk, which drives the phone calls.

The code on the chip averages the data and makes decisions about when a phone call request should be sent. There are set thresholds, unique to each plant, for minimum and maximum soil moisture.
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Based on sensor information, plants are able to place outgoing phone
calls to a nearby telephone and express their needs. All phone calls
are coordinated by Asterisk, an open-source telephone system. When a
plant’s microcontroller determines that the plant needs to make a
phone call, it contacts a PHP script with the plant’s ID number and
type of need. PHP then packages this information and passes it on to
Asterisk which generates the call. When the call is placed, an audio
file in played in the voice of the plant expressing its need.

Current call types are as follows:
-a request for water
-a confirmation of & thanks for watering
-a request for more water if initial watering was not sufficient
-a notification of unnecessary watering
-a notification of extreme need for watering when plant is excessively dry

In addition to the outgoing call system, you can call in and be
connected to the plants to learn more about them.