Those spades aren’t going to keep themselves in line.
As with any tool, especially one you frequently use outside, gardening implements require regular maintenance. I don’t just mean cleaning the dirt off when you’re done, though that probably wouldn’t hurt. I’m talking filing, sharpening, polishing, the whole nine yards. Dull tools won’t do their jobs even half as well as something in tip-top condition.
Shovels, spades, and trimmers, for example, require regular sharpening. My dad had a shovel when I was a kid, and he never sharpened it. That rusty piece of junk could barely pierce the ground, let alone dig a hole. Dull plant trimmers are dangerous to your plants’ health, as they could crush stems instead of cleanly cutting them. Get yourself a large file, clamp the tool in something sturdy like a vice, and sharpen those edges. Going back to shovels, make sure to sharpen the point and curve, but leave the sides alone. You want it to cleanly carve through the ground, but still firmly hold whatever dirt is sitting in it. If your tools are smaller and more delicate, use a smaller file or a whetstone.
As for non-bladed tools like watering cans or rakes, inspect them regularly for damage. A watering can with a hole in it isn’t especially dangerous, but it can be really inconvenient to have it leaking all over the place. Rakes’ teeth often warp or pop off after a while. If it’s too damaged, you might just have to suck it up and get a new one. Also, if you use something like a wheelbarrow to carry your tools around, inspect it once in a while to make sure no bugs or small animals have taken up residence. Again, not dangerous, but definitely inconvenient.