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Field capacity

Field capacity is how much water stays after drainage.

Speed
  1. Field capacity。
  2. Field capacity is how much water stays after drainage. Irrigating past it waterlogs the root.。
  3. Water the soil still holds after gravity has drained. Sand holds little;。
  4. clay holds much but may not give it to the root.。
  5. Water the soil still holds after gravity has drained. Sand holds little;。
  6. clay holds much but may not give it to the root.。

How it appears on the sheet

Water the soil still holds after gravity has drained. Sand holds little; clay holds much but may not give it to the root.

A sketch. Do not fertilise from the picture alone.

Common units

Usually % or g/g. Past the line is waterlog.

How to read the number

Water the soil still holds after gravity has drained. Sand holds little; clay holds much but may not give it to the root. Texture and OM set it. Below it the crop dries; stuck above it, roots smother Easy to mix up: Waterlog is water pushing air out; drought is water below what the soil can hold. Field capacity is the line between Field capacity is how much water stays after drainage. Irrigating past it waterlogs the root.。

Thresholds only, not a prescription. Rates live in the field guide. This page does not hand you a bag count.

What it looks like in the field

Water the soil still holds after gravity has drained. Sand holds little; clay holds much but may not give it to the root.

Don’t do this

  • Wet wilt irrigated as drought.
  • Watering past the field-capacity mark.
  • Waterlog is water pushing air out; drought is water below what the soil can hold. Field capacity is the line between.

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