Although no thresholds are available, an application of Lannate may be needed to control aphids and prevent husk quality problems. Fall armyworm moth activity has increased. All late-planted fields should still be checked during the whorl stage for fall armyworm feeding. Hollow heart of watermelon is the separation of the inner part of the fruit into distinct segments, which leaves hollow areas inside the fruit at maturity. It is known that this disorder does occur more frequently in the first fruit, and later sets should not have as much hollow heart.
Hollow heart is linked to excess nitrogen fertilization and delayed harvesting.
It occurs during conditions of rapid fruit growth, when the rind is growing more rapidly than the inner regions of the fruit. Excess irrigation may also contribute to the disorder. Although some varieties have a greater tendency to hollow heart, this year the problem has gone across many varieties. Avoiding excess nitrogen applications and crediting not only fertilizer nitrogen but residual poultry manure nitrogen needs to be considered. This probably had something to do with the heavy incidence of hollow heart this year.