Once the spring weather arrives many rose gardeners have trouble with rosebuds that don't open. Thrips are commonly the issue. Thrips can be difficult to deal with, but you can control them and save your rose blooms by following several easy steps.
First you want to determine that thrips are what is actually plaguing your roses. There are several different reasons your rosebuds might not be opening. Thrips are the most common, but it's best to be sure what you're dealing with before you act. Nothing is more frustrating than taking the time to control a disease or insect that doesn't exist. You definitely need to be sure of correctly diagnosing your problem before applying a chemical control.
Lets first double check your diagnosis. If a few rosebuds on the plant are opening and they appear brown or slightly chewed and damaged this is also a common symptom of thrips. Next you should take a non-opening bud and pry it open. If you see tiny white, black or brown scurrying insects those are thrips.
The first step is to cut off all of the unopened rosebuds and throw them away. This will remove many of the pests. Thrips are larvae laid into your rosebuds that then grow by sucking the juice from your unopened flowers. Once these larvae develop they head to the soil where they pupate into adult insects and then the cycle begins again.
Your next step should be heading to your garden center and checking for a product to deter or kill thrips. There are many choices from insecticidal soap to horticultural oil that are safe to use in your garden. It's best to attempt the least harsh treatment first, you don't want to harm beneficial insects that will eat the thrips and help you to gain control of your infestation.
Follow the package instructions for any chemical controls you choose to apply and be on the lookout for any additional rosebud damage in the future. With persistence you'll soon have your thrip problem under control. After a little bit of work and time your roses will be blooming beautifully again.