How to clean landscaping bricks

Spray close to the bricks with regular water and a strong pressure garden hose, ideally with switchable nozzels (jet, full, etc.) pointing away from the plants.

Best time is anytime the plants need water.

Is there something else other than regular dirt on the bricks?

Powerwash with water or a small amount of soap. Works great!

Please note: bricks sometimes have a sealer. If you powerwash it will remove this seal and the bricks will start to deteriorate. I learned this the expensive way.

Wet and forget is the easiest way

Use a pressure washer with plain water. You can do it any time of year, as long as it is not freezing outside.

If there are plants immediately next to the bricks that you want, then no, do not use any cleaner just yet.

For any cleaner to be effective on bricks, it must be scrubbed into the bricks first before being sprayed. Otherwise, it will just be washed off with the water.

I would try the strong jet setting on the regular garden hose first. In a short distance area, the pressure can be almost as intense as that of a low end pressure washer.

If this doesn't clean the bricks to your satisfaction, then post a picture of the problem area, and ask your question again.

You are welcome.