Mulches in California Vegetable Crop Production

Oct 28, 2010

Many food producers use mulches for weed, insect, and disease management and for water conservation to improve crop production .  Depending on specific production goals, growers use reflective plastic or cover crop mulches.

Most plastic mulch materials are made of either high- or low-density polyethylene.  They typically range from 0.3 to 0.79 inches thick (7.7 to 20.2 mm), 5 or 6 feet wide (1.5 to 1.8 m), and 555 to 1,138 yards long (60 to 1223 m). The additional benefits of plastic mulches in vegetable production include: crop earliness, increased yields, improved crop quality, and reduced fertilizer leaching in some cases.

Challenges with this type of mulch include: removal and disposal, higher production costs, specialized management and equipment for installation, and increased susceptibility to frost.

Use of cover crops as mulches is currently being refined and evaluated in a wide range of vegetable production systems.  Additional benefits of cover crop mulches in vegetable production include: enhanced nitrogen availability, reduced soil erosion, increased soil organic matter, reduced intercrop tillage, increased soil quality, and offset payment incentives possible through U.S. Farm Bill conservation programs.

Challenges with this type of mulch include: cooler temperatures above and below mulch, slower-maturing crops, cover crop mulch re-growth, specialized management and equipment in some cases, limited in-season weed management options, cost, and allelopathy (plant chemical interference) between cover crop and production crop.

UC ANR’s free Mulches in California Vegetable Crop Production publication is full of information on this subject with suggestions for further reading at the end.