And some of them are very fragrant.

The secret of success with these is never to leave a flower to go to seed.

They are not cut off by autumnal frosts.

On the contrary, you can take them up, and divide, and reset, and send a portion to other little gardens where they are lacking.
All mine (and they have been very gay this year and very sweet) I owe to the bounty of friends who garden _non sibi sed toti_.
Lastly, if there is even a very little taste and time to spare, surely nothing can be so satisfactory as a garden full of such flowers as (in the words of John Parkinson) "our English ayre will permitt to be noursed up." Bearing in mind these counsels: Make a wise selection of hardy plants.

Grow only good sorts, and of these choose what suit your soil and climate.