AUBURN UNIVERSITY, Ala. – Water management is one of the most critical issues in modern agriculture. Water resources have been critical to farmers since the advent of agriculture. Proper and timely irrigation is one of the first requirements of a sustainable integrated pest management (IPM) system. Mismanaged water in a vegetable garden or farm can lead to sick plants that makes them more vulnerable to pests. In a vegetable farm or garden, water can be managed with some simple and smart ways.
Dr. Ayanava Majumdar, an Alabama Extension entomology and plant pathology specialist, gives a few tips for water management in vegetable production from the IPM perspective.
Always Use An Irrigation System to Direct Water Close to Plant Roots
Any irrigation system is better than nothing at all, since the goal is to direct the water where the plant roots are. For example, a vegetable garden with soaker hose is better than a garden with flood irrigation that leads to the loss of top soil, nutrients, and chokes the plant roots. Although the use of soaker hose is not the best option for vegetable production, they are often cheap and readily available to the gardeners through the local stores. Today most vegetable producers use drip irrigation system that trickles water to the plant root zone. Sprinkler irrigation can be used for small vegetable plants but the risk of foliar diseases increases greatly along with uneven water application in the late growth stages.
Keep Vegetable Leaves Dry to Reduce Pathogens and Insects
Overhead or sprinkler irrigation wets the plant foliage that may be favorable for disease development. Splashing water off the plants may also result in the movement of pathogens between closely planted plants. There are certain benefits to overhead irrigation (for example, dislodging aphids from leaves or drowning spider mites) but loss of water to evaporation and risk of disease are greater threats in vegetable production. Use of soaker hose and drip irrigation system (i.e., low-pressure systems) under the plants reduces loss of insecticides applied to the plant foliage. This huge benefit really for organic producers who may use bioinsecticides for pest management. Vegetable field with drip irrigation system also make it possible to inject systemic chemical insecticides through the drip line reducing the need for overhead applications.
Use Mulch to Hide Drip Lines or Soaker Hoses
It is a good idea to use mulch on the top soil to hide the irrigation system and reduce evaporative loss. Mulch will also retain soil moisture, reduces weed seed germination and soil erosion. In a garden situation, mulches can also absorb excess pesticides and prevent them from wash-off or leaching. A variety of natural mulches are available in the stores today – but first do your homework and check whether they are suitable for your farm or garden. Pay attention to the thickness of the mulch as excessive watering under a thick mulch can be detrimental to the plants and/or harbor insect pests such as cutworms and armyworms.
Save On Costs With Chemigation
Directed water and insecticidal applications (also known as chemigation) with drip irrigation or other contained systems can drastically reduce need of insecticides and labor costs. Record your garden or farm activities in order to document the effectiveness of your irrigation system. Solve your irrigation challenges with sound logic and common sense. When in doubt, call your nearest extension office for help with designing suitable irrigation and pest management systems so you can enjoy a plentiful harvest.
For more information, visit Alabama Extension online at www.aces.edu or contact your county Extension office.