Question
I live in California, we have a lot of rain now. I've just pruned back my roses. How should I feed them? when to start? my roses are 9 years old, they are really good in spring and weak in summer, maybe I don't feed them right?

Answer
The general rule for fertilizing roses, no matter where you live, is to give the roses something to encourage more growth when they start to leaf out in the spring. I am assuming your roses are either hybrid teas or floribundas. So whenever you see your roses starting to make new growth, you then help them by applying some fertilizer. After they have finished the first flush of flowers, they will be making more growth to support the second flush and that is when you give them a another application of fertilizer. That is all the rose will need for the year. Never give a rose bush any fertilizer when it is hot in the summer because in the high heat, a rose goes into partial dormancy and the roots won't be able to take the fertilizer up and even if they could, that is when you would see leaf burn. In hot areas, roses never look their best in the middle of summer. Most rose gardeners will tell you that their rose are wonderful in the late spring and then again in the fall. But during the summer the roses are a hit and miss in regards to flowering well.
A rose will need a lot of water at certain times. One of them is when it is making new growth and the other is when the heat of summer goes higher. In your area I wouldn't encourage a rose to grow in high heat, just let them rest and then when the temperature comes down to normal, you can give them some food. Another good idea is to mulch your roses as roses love cool roots and a mulch will give them that. It also saves you time and effort in watering and helps them go through a hot summer much better.