Do not rinse the plants with hot water. You will do more harm to the plant than good. A simple rinse under cold water will suffice.
As far as the crickets go, you can try the glass bowl trick. Dust the crickets, place them in a glass bowl about 2" high or so and place the bowl in the tank or place the bowl in and then add the crickets. The order is not important, the important thing is that the crickets cannot climb glass and stay in the bowl instead of roaming the tank.