Plant watering system

An apparatus for providing fluid to plants planted in soil, the apparatus comprising:

• a fluid providing structure adapted to selectively provide fluid to the soil;
• a probe structure, comprising an end, a first conductor including a first conductor portion and a second conductor comprising a second conductor portion, the probe structure being adapted to maintain the first conductor portion and the second conductor portion in a spaced apart relationship proximate to the end so that soil surrounds the first conductor portion and the second conductor portion when the end of the probe structure is placed in the soil;
• a first resistance measuring structure adapted to effectively determine the electrical resistance between the first conductor portion and the second conductor portion of the probe when placed in soil;
• a reservoir structure adapted to hold fluid away from the soil, the reservoir structure having a reservoir level detector and a second resistance measuring structure adapted to effectively determine a reservoir water level;
• an input structure adapted to allow a user to choose a calibration point in time;
• an indicator structure adapted to indicate the information about soil moisture level to users, the indicator structure having a first light and a second light,
• a computer having a microcontroller and a controller structure connected thereto, the computer programmed with instructions to operate the controller structure to:
• control the selective provision of fluid by the fluid providing structure,
• at the calibration point, control the resistance measuring structure to effectively determine a calibration resistance to be received by and stored in the controller structure,
• subsequent to the calibration point, control the resistance measuring structure to effectively determine a subsequent resistance to be received by the controller structure,
• compare the subsequent resistance to the calibration resistance to determine information about the soil moisture level,
• controls the second resistance measuring structure to effectively determine a reservoir resistance and compares the reservoir resistance to a predetermined threshold value to determine whether the fluid level in the reservoir is low;
• the computer further programmed to operate the controller structure to control the first light to be on when the comparison operation determines that the subsequent resistance is greater than the calibration resistance by at least a predetermined first threshold amount;
• and
• the computer further programmed to operate the controller structure to control the second light to be on when the comparison operation determines that the subsequent resistance is less than the calibration resistance by at least a predetermined second threshold amount.