Question
I have always heard that knockout roses are very tolerant and it's almost impossible to kill them.  WELL,,, I planted 5 of them this Spring and they are doing ok,,, new growth on all of them, I dead head them often, but they all have yellow leaves.  I live in Houston and it's been very hot with no rain, but our sprinkler goes off every other day.  Am I watering too much?  I want them to look good, but am sad that they will die.

Answer
If the amount of questions I get concerning the problems with Knock Out roses is any indication, then Knock Out roses are no different than any other roses. One of the things they don't seem to tolerate is high heat without a lot of water. Sprinklers are okay when the roses are mature. However when they have just been transplanted, they need twice as much water and hand watering is a good idea when the temperatures are high. The roses are under stress because of the heat and will get yellow leaves but when things return to cooler summer temperatures, the roses will also start to grow healthier and not have yellow leaves. The roses will not die even if they drop all their leaves, they will make new ones when the weather is cooler. Just make sure they do get a lot of water.