Getting rid of rats from my garden...suggestions?

My mom is not going to like this post... I wonder if she would even visit us anymore. She is terrified of rodents: mice, rats, and even squirrels. Many years ago, when my parents were newlyweds, my mom fled after seeing a rat in their apartment. She refused to return unless my dad got rid of them. And my dad did, he used fried fish and traps. Later, they even adopted a cat.
Fast forward many years later, I can't believe I'm facing a similar problem.

A bit about out garden:

The garden is located at the sunset district of San Francisco, very close to the ocean. The natural soil is very sand-like, so the grass you see in the picture is not a natural occurrence. The place where we are having a rat problem is not here, but the two alleyways at both sides of our house, where there are two raised planters installed. A month ago I transplanted my darling seedlings into the South facing planter, and realized we were not alone.

This picture was taken 3 weeks ago, now almost all the leaves are gone, chomped off, eaten...

Until Ming saw the rats last week, I had been in denial, it has got to be bunnies or birds. Then I saw them with my own eyes, and I realized we have to do something. We researched online and asked around for advice and came up with 3 quicker solutions and 3 tougher ones.
Easy ones: spray chili water over the plants, spray fox/wolf urine around, and plant odorous plants around the garden,  such as garlic, onions, and chives, I read rats don't like mint either.
Tough solutions: traps, the ones that would kill the rat. humane traps, then release them as far away as possible, or, we can buy a motion sensing electronic owl that hoots... Since owls are a natural predator, rats would stay far away from the garden.

Progress: I am reluctant to put animal urine in the soil which I grow food, so I went with solution 1 and 2. So far it seems the chili water worked, the rats stopped eating my plants at the rate they did previously. As for growing odorous plants, I am not so sure if it worked. I mean, the rat snapped off the green shoot of a scallion but didn't eat it...  either way, both methods didn't stop them from frequenting my garden, and I certainly want them gone!

So it leaves us taking the rough route. Kill? I'm not sure if I want to do that. Trap? I don't want to put a rat in our car, and I certainly do not want to walk around with a rat in a cage. The electronic owl, read online reviews and it doesn't work that well with rats...

Suggestions?