It's a good idea to change your fishing line at least once a year. And most anglers prefer to do this before they start the spring trout fishing season. This is when they're pulling out all of their tackle to make sure they have everything they'll need in the upcoming months.
Over time, your line is weakened by the sun and snags which stretch the line. It can also become stained from the water and other dirt and debris can help weaken the line. In short, it becomes brittle and worn out over time. And this can result in losing that trophy size trout!
Many anglers will change their lines more frequently than this since they tend to use the same rod and reel for different fishing conditions. But at the very least, you'll want to be sure and change your fishing line at least once per fishing season (or once a year).
Don't forget to clean the reel too once you have all the old line off it. Give it a good rinse with warm water. Use and old toothbrush or Q-Tip to clean hard to reach places. If you're mechanically inclined, you might even want to take the reel apart and clean the gears (but be sure you can put it back together again before doing this).
I would only suggest taking apart your spinning reel if you're using a higher-end reel. Always check the manufacturer's site for specific instructions on caring for your spinning reel. Using too much grease or oil could end up being worse than having left things alone.
When putting new line on the reel, you'll generally want to use 4 or 6 lb test line for trout fishing. You can also use 2 or 8 lb test for trout fishing, but these lines are generally used for specific lakes or rivers where a lighter or heavier line might be warranted.
If you've never changed your fishing line before, it's really easy. The trick is to pay attention when putting the line on the spool. Thread the line through the eyes of the pole first. Make sure the line goes under the bail before tying it to the spool. If done properly, you should be able to reel new line onto the spool.
Reeling will go much faster if you stick a pencil through the new line spool and have somebody hold it while you reel.
While this may seem like a hassle to some, having fresh line will help ensure you're able to land the big trout this season rather than lose him to a broken line!
For more trout fishing tips, check out our complete beginner's trout fishing eBook.