Jim, I feel that is the reason I water so, much here!with the 15 chickens ,going around my plants... I need to water down everthing so to speak..but I feel the yuccas are growing faster .but I hope that does not hurt them in winter.with so much in the soil but this is year 3 of the free range chickens year around and no bugs or ticks ,ect they eat yellow jackets too.