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Irrigation, Soil & Fertility TimingSalinity Management Calendar
Salt problems build slowly and show up as slow germination, stunting and wilting in fields that seem to have enough water, so a calendar of testing and leaching beats waiting for symptoms.
Key points
- Test irrigation water and soil before assuming a cause.
- Salt-sensitive crops show trouble first; tolerance varies by species and stage.
- Leaching needs low-salt water and soil that drains.
- Retest after treatment to see what changed.
- Check local water use and drainage discharge rules.
Where do soil salts come from?
Salts arrive in irrigation water, in some fertilizers and manures, from shallow groundwater and from the parent material of the soil itself. When water evaporates or is taken up by plants, the salts stay behind and concentrate near the surface or in the root zone.
Texas A&M AgriLife Extension notes that irrigation water is a major source of salt buildup, which is why testing it is the first step.
Water quality changes through the season. Wells can show different salt levels in dry periods than in wet ones, and surface water sources can vary with runoff. Test at several times of year, especially in a dry stretch when salt levels often peak.
How do you recognize a salinity problem?
Typical signs include patchy emergence, stunted plants, leaf edge burn, wilting despite adequate watering and white crusts at the surface. Salt-sensitive plants suffer first, and tolerance varies widely by species and growth stage.
Many problems look similar, including compaction, disease and sodium-related structure issues, so confirm with a lab. A soil electrical conductivity test and a water analysis, along with sodium information, are the standard starting points.
A field with a shallow water table is a special case. Water can rise through the soil and bring salts with it, so drainage and water table management matter as much as irrigation. Fixing that usually involves regional drainage planning, not a single field fix.
When should you leach salts?
Leaching means applying enough low-salt water to move salts below the root zone. Timing depends on climate and crop. Many growers leach when the crop is not growing or is least sensitive, and when the soil is warm enough to drain well, for example between seasons or before planting a sensitive crop. In humid regions natural rainfall often does this for you.
For example, if you farm in an irrigated dry region and your last crop left a salty surface, plan a leaching irrigation before the next planting and retest afterward to see whether it worked. AgriLife notes that very saline soils may need several rounds, and that testing after each round shows progress.
If you see white crusts in low spots, mark them and sample them separately from the rest of the field. Averages can hide a serious problem in a small area.
Why does drainage decide the outcome?
Leaching only works if water can move down and away. Clay content, compaction, high sodium and a shallow water table all block it. In such cases, applying more water can raise the water table and make things worse.
Fixing drainage, breaking hardpans where appropriate and avoiding traffic on wet soil are long-term jobs. Ask extension about sodium-affected soils, which are managed differently from salty soils, and about local water use and discharge rules before you move salty drainage water.
What does a salinity calendar look like?
Before the season, test irrigation water and soil, and choose crops or varieties that fit the conditions. During the season, favor irrigation schedules that avoid repeated shallow wetting, since that concentrates salts near seedlings. After harvest, retest and plan leaching or gypsum-type amendments only if the soil test and an adviser support them.
Keep a record of water quality, soil test results and treatments by field. Patterns across years tell you whether your approach is holding salts steady, lowering them or letting them creep upward.
How do crop choices and varieties help?
Salt tolerance varies a great deal among crops and sometimes among varieties. Where salinity cannot be quickly reduced, growing a more tolerant crop is a practical response. Extension publications list relative tolerance for many crops, and seed dealers may know local trial results.
Seedlings are often the most sensitive stage. Planting on the shoulder of a raised bed, where salts accumulate less than at the center, is a technique described in irrigated regions. Ask a local specialist whether it fits your system.
What mistakes make salinity worse?
Frequent light irrigation leaves salts near the surface and the seed. Using high-salt water without enough leaching builds the problem over seasons. Over-application of salt-bearing fertilizers or manures adds to it, and so does poor drainage.
Another mistake is treating sodium problems like salt problems. Sodium-affected soils lose structure and seal, and the fix involves different amendments and careful water management. A lab report that separates the two is worth the cost, and a certified crop adviser can interpret it.
Sources and further reading
Last reviewed: November 2026. Educational information, ranges only. Confirm timing with your county extension office.