Overwatering and waterlogged soil

About

Roots need air as well as water. When soil stays soggy from watering too often, poor drainage or flooding, roots suffocate and die, and the plant can no longer take up water even though the soil is wet.

Also called overwatering, water excess or uneven watering, water excess, too much water, waterlogging, waterlogged soil, drowning, wet feet, poor drainage, aeration deficit

How to recognize it

Symptoms

Growth slows, leaves yellow, and plants wilt or show scorched leaf edges, which looks a lot like drought. Dead roots are brown inside and their outer skin slips off easily; healthy roots are creamy white. Soggy soil may smell sour or rotten, and trees can show leaf curl, leaf drop and branch dieback.

Often confused with

It looks like drought stress, so check the soil a few inches down before watering more. Root rot (see Root and crown rot) and wilt diseases often move into drowned roots; edema blisters are another sign of too much water.

Worse when

Watering too often, heavy clay or compacted soil, low spots and downspouts, pots without drainage, and long rainy spells.

How it spreads

It does not spread from plant to plant, but weakened roots invite root rot organisms such as Phytophthora.

When

Any time; worst in rainy spells, in spring on heavy soils, and on houseplants watered on a schedule.

What to do, gentlest first

This is not an infection, so sprays for diseases won't help. Fix the cause below.

1. Check before you water Prevent

   The surface dries first, so dig down a few inches with a trowel or probe and water only when the root zone is drying. Water deeply and less often, and fix leaky spigots and downspouts that keep beds wet.

   Plants that droop in hot afternoon sun often perk up by evening on their own; that is not always a sign they need water.

2. Improve drainage or pick the right plant Prevent

   Work compost into heavy clay, use raised beds for annuals and vegetables, and plant trees and shrubs a bit shallower in wet spots. Put water-loving plants in low, damp areas.

   If soil is still squishy six or more hours after rain or watering, drainage is poor.

3. Let it dry and trim the dead By hand

   Stop watering until the root zone dries. Knock a potted plant out of its pot to look at the roots, and cut off dead branches on trees and shrubs once you see them.

   Fertilizer does not fix drowned roots. Most trees and shrubs come through floods that drain within about a week.

Plants it affects

Colorado blue spruce, Eastern redbud, Eastern white pine, Sugar maple, Tulip tree