Question
QUESTION: I live near Raleigh, NC, and I believe it is Zone 7.  I planted about 30 Knockout Roses in April in newly established flowerbeds.  The blooms at first were large and beautiful.  I fed them Miracle Grow Bloom Booster time released fertilizer.  What has happened is there are lots of stems growing and lots of buds, but the buds are small, and when they bloom the roses are very small, not large anymore.  They look like miniature roses.  The buds seem also to be opening prematurely and dying quickly.  This is true for all 30 of them.  What are they lacking?  They have plenty of full sun and water.  Thank you.

ANSWER: When all of your plants are suffering from the same symptoms, then it is usually something the gardener has done if al other conditions are okay for the plants. Hard to make a suggestion as I can't see the roses but here is what I think may be causing the problem. Usually it is not a good idea to give any type of fertilizer to newly planted roses although rose books always tell you to do it. The reason is that roses always go under a little tress when they are moved into a new location even if they are transplanted into a perfect one. Because they are under stress, their roots sort of semi shut down and will only take water and organic type nutrients up. In a few weeks they settle in and start to put out normal growth. Most rose fertilizers are fine for roses and don't cause any problems. With the Knock Out roses they will bloom well without any extra type of fertilizer. The bloom booster type of nutrients is VERY high in phosphorous and is usually too strong because it is far more than what the rose needs. Phosphorous causes a build up in the soil that will over time kill the beneficial bacteria as well as the micorrhizal fungus, these two, as well as others, break down the fertilizer or any other nutrients in the soil, so the rose can use it. If Miracle Bloom Booster is used, it should not be used on newly planted anything and only at half the strength and in a liquid form. I would only use it for plants that have been in the soil for at least six months.

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QUESTION: I didn't fertilize them for the first month, but I didn't know it should have been six months.  The fertilizer was a slow release, which is supposed to last for three months.  I read in a book that roses love a lot of water.  At first I was giving them a good drink every evening, because our weather was a hot 95.  They were doing fine, but I wondered if I wasn't watering them too much, so I cut back to every other day or every three days.  The book said small flowers could result in not enough water.  Could you tell me exactly how to properly water these roses?  How much water and how frequently?  Thank you for your help, I really appreciate it.

Answer
You have given me the reason why your Knock Outs are making smaller flowers. It is the very high temperature that is putting the plants under stress, which means they will conserve their energy and not make perfect blooms. Watering them well was a good idea because of the high heat. Under normal weather conditions, a Knock Out rose would need about a bucket of water per week. They like to have a good drink and they dry out. I also wouldn't give them any fertilizer until the weather cools down a bit. The combination os high heat and chemicals in the soil will cause problems. Your soil probably contains all that the roses need right now to do well. Wait until the heat calms down and you will see a big difference in the roses.