Pulling weeds can spread weed seeds and disturb the soil, leading to seed germination. Pulling weeds can also trigger growth in weeds that reproduce through their root systems—disturbing the roots without fully removing them may cause more weeds to grow from the roots.

No, it's not really possible to completely prevent weed growth. Weeds are incredibly resilient—all they usually need is a tiny bit of dirt to sprout, so their eventual appearance is pretty much inevitable. However, you can definitely keep them at bay by getting rid of weeds as soon as you notice them. The longer you let them sit and grow roots, the more they'll spread.

The main problem with crabgrass is that it produces thousands of seeds that can remain dormant until the following season. To get rid of it, you have to remove existing plants before they have a chance to spread seeds and stop old seeds from germinating.

Jet washing can wash away weeds without bending or kneeling to pull them. However, the results will likely be fleeting because the weeds will return unless you use a stronger method that takes them out at the root. Use a jet washer for short-term weed removal, but use a stronger method if you want to get rid of weeds for good.