If you take good care of your blinds, you can make them last up to 8 years. This is a lot of time, and it allows you to make the most out of your purchase. Of course, just dusting your blinds once every few months will not cut it if longevity is the goal for you. At the same time, if your blinds are already old, are generally of bad quality, or are thrifted, then that might factor into its overall longevity as well. If you are interested, you should look into the cheapest blinds for windows read review so that you can buy affordable blinds, or learn how to make them look good as new.
You cannot let dust gather and sit on your blinds for long durations of time because that will end up not only look unattractive, but it will also end up weakening the color of your blinds overtime. You want to ideally dust off, or vacuum your blinds once every month to keep them looking fresh and to prevent dust and debris from settling into the material.
You should also spot clean your blinds if there are spills, stains, or dirt on it. You do not have to go for abrasive cleaning materials if your blinds are made of material other than fabric. With fabric blinds, you can take it a step further and give the blinds for bi-annual dry cleaning if your cleaner does happen to offer that service.
Roller blinds can be cleaned with just a damp cloth or sponge. Do not manhandle the roller blinds when you are cleaning them because that will end up potentially ruining their shape and you can end up with blinds that have their form affected, which can then mean your blinds not rolling in or out properly when you do unravel them later.