Hopefully you should. They have an upcoming rose festival. So there should be roses.
They do have a huge variety of roses at the garden. Some roses do bloom into mid October just in time for the Rose parade that will be happening on October 13-16. Call the Rose museum and they will be able to help you if you would like to know more about planning a visit. To me its beautiful to visit the Rose garden in every season.
Yes, I'm pretty sure they said the best times are April and October but I would call to be sure. There is someone there working throughout the week that can tell you for sure.
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