The warm, slightly peppery taste of rocket, or arugula, enhances salads. It doesn't add crunch, like a crisp cos lettuce leaf, nor bright colour, like tomatoes or radishes, but it makes its presence felt in that subtle flavour and delightful heat that is quite unique.
The good news is that it's very easy to grow - it doesn't need especially good soil, nor even full sun. And once you've grown it once, you should never need to buy seeds again, because it's so easy to save your own:)
Allow one plant to flower, the white, star like flowers aren't particularly stunning, but they aren't unpleasing either. As the flowers die back, you'll see tiny green pods developing. By all means snip a few off and add to your salad plate - they also have that delicious warmth of the rocket leaves.
The pods will grow to about an inch or so in length, and as the summer progresses, they will turn brown and dry. This is when you go out with your paper bag, and harvest the crisp seed pods.
Bring them indoors and carefully split the pods. I say carefully because if you're rough with them the seeds will catapault all over the floor - such a waste! I put a sheet of paper down and collect them on that, then pour them into an envelope to store them.
You'll see that some of the pods develop speckly black marks, this doesn't affect the seeds, don't worry. You'll get more than enough seeds from one plant to see you through next year - unless you've a large family, in which case, allow a couple of plants, or even more, to set seed - keep picking the leaves on the others so that they'll continue to grow.
Successional sowing, every few weeks, will ensure that you have young, vigorous plants to enjoy.