As you probably know the hurricane season started last week and right after that we had heavy rainfall in our area. Almost all citrus groves are located on high water tables with poor drained soils. With recent heavy rainfall, now the soil is water-saturated and cannot drain more water. Unfortunately, the tropical storm Cristobal is forecasted to bring even more rain to east central Florida, including the following areas, Indian River, Martin, Northern Brevard, Okeechobee, Osceola, Southern Brevard and St. Lucie.
These tropical storms bring a lot of frustrations and stresses other than rain for citrus growers because water management on these soils is difficult and expensive. On these soils, drainage is as important as irrigation, it means that water management should be started even before hurricane season.
Symptoms of flooding injury may show up within few days or weeks, but usually can be seen when the soil dries. One of the first symptoms is leaf wilting due to the lack of enough water coming from damaged roots. Then leaf drop and twig dieback occur. Chlorosis patterns may develop, and tree death may occur.
Recommendation
It is always advised to have a plan before grove establishment instead of improving drainage in existing groves, that is very difficult and costly.
- Do not depend on rootstock tolerance to waterlogging
- Do not disk a grove when trees were injured by flooding
- Reduce Irrigation amounts and increase frequencies
- Take soil sample to evaluate fungal invasion. If there is a Phytophthora problem, the use of certain fungicides can improve the situation
- Always keep all drainage systems (canals, retention/detention areas, open ditches, subsurface drains, beds, water furrows, swales and the pumps) clean and operational to prevent prolonged waterlogging
For more information please read the EDIS article.