How to Manage Pests
UC Pest Management Guidelines
(Reviewed 1/07, updated 1/07)
Optimal physical and chemical soil conditions are required to
establish healthy plants. Poor soils require remedial action in order to
establish healthy plants; this may take many years and can be expensive. Use
the table below to compare tomato field requirements with the conditions of
your prospective site. If there are specific site problems, you will need to
determine if remediation is feasible. Proper field preparation is also essential
for minimizing fertilizer and pesticide runoff.
|Hardpan, compacted soils
||Tomato grows successfully on a range of
soil textures, but deep, loamy, well-drained soil with organic matter is preferred.
||Irrigate more often
|Clay soils with poor aeration
||Install drainage tiles
|Uneven topography, ditches,
- Precise field leveling appropriate for irrigation
system and providing for drainage at tail end.
- Use of subsurface drip irrigation.
- Install drainage tiles.
|Nutrient deficiencies such as
nitrogen, phosphorus, and
|Fertilize if soil tests show deficiencies.
||Low pH: lime the soil
||High pH: reclaim (see sodic soil below)
||Reclaim: leach excess salts below the root zone.
||Sites with excessive salts require major modifications that can be expensive.
|Remediation requires adequate soil calcium
to replace sodium on soil cation exchange sites. If soil is low in calcium, apply gypsum (CaSO4). If soil has free lime (CaCO3)
apply sulfur, which over time lowers soil pH and increases calcium solubility. In addition to ample soil calcium,
sufficient leaching volume (from irrigation or rain) is required to move sodium below the root zone.
||Sites with excessive sodium require major
modifications that can be expensive, and time consuming. Sodic soils are unsuitable for tomato production until effectively remediated.
|Seed or seedling pests (for example,
||Plow and disc old crop, cover crop, or other plant material that can harbor pests.
|Pathogen, nematode or weed
||Soil solarization; deep plowing to destroy sclerotia.
Apply preplant herbicide in fall or just before planting.
Just be fore planting in San Joaquin Valley, preirrigate the field and cultivate germinating
Deep plow (9 to 10 inches) with a moldboard plow to reduce nightshade and nutsedge populations by burying seeds and tubers.
UC IPM Pest Management Guidelines:
UC ANR Publication
W. T. Lanini, Weed Science/Plant Sciences, UC Davis
T. K. Hartz, Plant Sciences, UC Davis
R. M. Davis, Plant Pathology, UC Davis
C. J. Rivara, Calif. Tomato Res. Institute
E. M. Miyao, UC Cooperative Extension, Yolo Co.
F. G. Zalom, Entomology, UC Davis
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