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Cornell Commercial Vegetable
Production
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Nutrient deficiency signs
by Stephen Reiners
Associate Professor in
Horticultural Sciences
During cool wet growing seasons, vegetable crops often
suffer nutrient deficiencies that aren't seen as often in New York during
normal growing seasons. In many cases, the deficiencies are caused by
waterlogged fields or excessively low pH.
The soil pH can have a significant effect o the availability
of the nutrients needed by plants. A pH below 5.5 can cause deficiencies
of calcium, magnesium and molybdenum.
A pH above 7 will lead to deficiencies of copper, iron, zinc
and manganese. Boron may be limited at both excessively high and low
pH.
Foliar sprays of these minor elements can be helpful to
overcome temporary deficiencies caused by excessive rainfall.
The following table lists typical deficiency symptoms and
when they are most likely to occur.
| Nutrient deficiency
symptoms |
| Nutrient |
Symptoms |
Occurrence |
| Nitrogen |
light green or yellow older
foliage |
soils with excessive leaching |
| Phosphorus |
stunted plants and purplish leaves |
cold, wet soils in early spring; low pH
soils |
| Potassium |
brown leaf margins and leaf curling. |
light soils with excessive leaching |
| Calcium |
stunted plants, stubby roots, causes
blossom end rot of tomatoes, tipburn of cabbage & lettuce,
brownheart of escarole, celery black- heart, carrot cavity spot |
on very acid soils; soils with high
potassium levels; dry soils or excessively wet soils. |
| Magnesium |
yellowing between veins of older
leaves |
light, acid soils; soils with high
potassium |
| Sulfur |
yellowing of young leaves, stunted
plants |
low OM, sandy soils |
| Boron |
growing points dieback and leaves are
distorted; center of crucifer stem becomes hollow and brown |
soil pH above 6.8 or below 5.5; plants
with a high boron requirement (beets, crucifers); sandy soils with
low organic matter |
| Copper |
yellowing of leaves which become thin and
elongated, causes soft onion bulb with thin scales |
mostly on muck soils; high pH soils |
| Iron |
light green or yellow foliage on
youngest leaves |
soil pH above 6.8; low OM, excessive
P |
| Zinc |
rust colored spots on seed leaves of
beans, green and yellow striping of corn, yellowing of beet
leaves |
high pH and low organic matter; cool wet
soils in spring; may be related to high phosphorus
fertilization |
| Manganese |
mottled yellow areas appearing on younger
leaves first. In beets, foliage becomes deeply red. |
soil pH above 6.5 |
| Molybdenum |
distorted, narrow leaves, some yellowing
of older leaves; whiptail leaf symptoms in cauliflower but also seen
in cabbage some years; leaf edges are curled and ruffled. |
very acid soils |
Cornell Commercial Vegetable Production
Comments or questions?
Contact:
Anusuya
Rangarajan
Statewide specialist for
Fresh Market
Vegetable Production
ar47@cornell.edu
Department
of Horticulture
121 Plant Science Building
Cornell
University
Ithaca, NY 14853
(607) 255-1780; Fax: (607)
255-9998
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