Warm Weather Is Here, but It’s Not Summer Yet: Irrigation and Planting Decisions for Early Season

Nevada’s winter 2025–26 was record-warm. The Nevada State Climate Office reports that persistent above-normal temperatures through December, January, and February pushed the statewide average winter temperature 5.5 °F above normal, making it the warmest winter on record. Precipitation was uneven, with an active storm period in late December, which was followed by a month-long dry spell in January and early February, and the season ended with low snowpack in many locations. As of March 2026, 66 % of Nevada remained in “abnormally dry” or drought conditions, and the spring outlook favors above-normal temperatures with only slightly below-normal precipitation. In other words, early-season heat does not mean that summer has arrived. Soil temperatures are still low, the frost risk remains, and the state remains drought-vulnerable. This guide aims to help you avoid costly mistakes and protect crops, soils, and irrigation systems as spring unfolds.

Plant according to soil temperature, not warm ambient air temperatures

Warm-season crops germinate poorly in cold soil. Colorado State University notes that soil temperature at four inches deep, measured at 8 a.m., is one of the best guides for spring planting time, and that warm-season crops should be planted only when soil temperatures are above 50 °F. Planting by soil temperature ensures that seeds germinate quickly and reduces disease and pest pressure. 

Beware of false springs; a week of 80 °F afternoons does not eliminate frost risk. The spring outlook calls for above-normal temperatures but also hints at a possible pattern change and increased precipitation by the end of March. Look at the long-term forecast and try to be realistic about the season. Always keep an eye on forecasts and plan your planting activities accordingly.  

Do not irrigate because of warmer ambient air temperature

Warm days in March can be deceptive as the hot air heats the soil surface quickly, but the underlying root zone warms slowly and still holds winter moisture. Over-watering when soil temperatures are cold wastes water and can damage crops by encouraging shallow rooting and disease. Instead of reacting to a hot afternoon, base your first irrigations on soil moisture, crop stage, and soil infiltration, not on air temperature alone. Instead, check rooting depth and crop demand, because Oregon State University (OSU) explains that an irrigation program must match the crop's changing demands with the water supplied. 

Make use of soil moisture tests before watering. You can do this by digging a small hole 3–4 inches deep; if a handful of soil can be squeezed into a ball that holds together, there is still adequate moisture, and irrigation can wait. Soil probes and tensiometers provide more precise measurements, as noted by OSU, that the simplest method to assess water availability is a soil probe that shows moisture distribution throughout the profile. 

Adjust for soil type and infiltration because sandy soils absorb water quickly but store little; clay soils hold more water but have slow infiltration and are prone to runoff. OSU’s irrigation guide explains that sandy soils have high infiltration but limited storage, whereas clay soils have lower infiltration but higher water-holding capacity. On clayey or compacted soils, it's recommended to cycle-and-soak irrigation, applying water in short cycles with soak periods in between, to minimize runoff and ensure water infiltrates. Where irrigation water is regulated and/or limited due to drought means rationing water to crops over a longer and potentially hotter growing season. Consider season-long water requirements to decrease the risk of late-season water shortages. 

Also, rather than basing your decisions on daily highs, monitor evapotranspiration (ET), which combines crop water use and surface evaporation and is driven by weather and canopy development. Normally, early spring ET is much lower, so irrigation intervals can be longer even when afternoon temperatures are high. 

Inspect the system before the first full run

A warm spell is the perfect time to perform maintenance on irrigation infrastructure. Before turning the water on, inspect all lines and emitters for leaks, clogged nozzles, and proper pressure, and flush drip lines to remove accumulated debris and salts. Check nozzle wear, arc, and tilt on sprinklers to ensure uniform distribution, and repair or replace worn parts. Use this checklist:

1. Walk the system – Look for cracked pipes, broken risers, and missing gaskets. Repair any leaks to prevent water loss and uneven application. 
2. Flush and clean – Open ends of drip lines or laterals to flush out sediment and salt deposits. Remove and clean filters, emitters, and sprinkler nozzles. 
3. Check pressure and coverage – Use a pressure gauge to confirm system pressure matches design specifications. On sprinklers, verify the arc, tilt, and nozzle size so that each circle or strip overlaps properly. 
4. Calibrate application rate – Catch-can tests or soil probes help verify how much water is being applied per hour. Adjust timing to avoid runoff on heavy soils and ensure deep watering on sandy soils. 
5. Plan repairs now – If system components are worn or outdated, schedule repairs or upgrades before demand increases. Drip systems may need emitter replacement or line flushing, while sprinklers may require new nozzles or pressure regulators. 

Scout weeds and early pests 

Warm weather stimulates both crop growth and weed germination. Early weed removal prevents competition and reduces weed seed production. Prevention is the least expensive method of invasive weed control, and early detection and immediate eradication reduce long-term costs. For pastures, it is recommended to walk the fields early to identify and manage weeds. Pest pressure also increases with warm temperatures, so watch for aphids, thrips, and spider mites on tender new growth and control them if necessary. 

References

1. Bubl, C. (2010, March; reviewed 2024). Irrigation management basics. Oregon State University Extension Service.  
2. Kratsch, H. (2010). Irrigating (watering) your vegetable garden (FS-10-16). University of Nevada, Reno Extension. 
3. Larson, P., Vance, L., & North, D. (2025, January). April monthly gardening guide for Pima County. University of Arizona Cooperative Extension.
4. Perry, B., Albright, T., & Dmitruk, G. (2026). Nevada winter quarterly climate report and spring outlook: December 2025–February 2026. Nevada State Climate Office, University of Nevada, Reno.
5. Smith, E. (2023, April). Spring pasture to-do’s. Oregon State University Extension Service. 
6. Whiting, D., & Jones, K. M. (2017). Irrigation management (GardenNotes No. 260). Colorado State University Extension. 
7. Whiting, D., O’Meara, C., & Wilson, C. (2018; reviewed 2024). Vegetable planting guide. Colorado State University Extension. 
8. Wilson, R. E., Johnson, W. S., Swanson, S., & Donaldson, S. (1999). Nevada’s war on weeds, step 5: Avoid exploding weed populations with prevention and early detection (FS-99-79). University of Nevada, Reno Extension.