The work takes place at the Mojave Bloom research compound in Las Vegas, with sensor stations in the yard, the garden beds and the trees. Results are compared with the official weather station at the airport (KLAS).
Small sensor stations log air, soil and light every 30 seconds in different parts of one yard.
Chill hours are winter hours below 45 °F. Many fruit trees need hundreds of them before they bloom well. Higher neighborhoods have cooler nights and more chill: about 3.5 °F cooler for every 1,000 feet of elevation. The east side of the valley is already at or near zero.
Estimated winter chill hours, calibrated to the 2020s Las Vegas climate. Bars show the typical value; lines show the range inside Summerlin and Henderson. Higher ground outside the valley gets more: Red Rock Canyon about 590 hours, Mt. Charleston 900 or more.
Weather stations measure air in the shade. Buds sit in the sun. On a sunny winter day, a branch can run far warmer than the air, and warm hours cancel chill.
A plant is adapted to the rain where it evolved. The driest parts of the valley supply about 2.1 inches of rain a year that plants can use. The rest has to come from irrigation.
Minimum extra water (inches a year) = lowest yearly rain in the plant’s home range − 2.1. See the water matrix.
Research on how irrigation water behaves in native and amended soils, and how fast it evaporates from the soil depending on temperature and air movement.
The result is recommended irrigation practices for the valley that are consistent with the Southern Nevada Water Authority (SNWA) watering schedules. See the paper Optimal Irrigation Timing and Practices for Desert Landscapes in Las Vegas, Nevada.
BEST Academy