About where in Libya is your garden going to be, Hanaina? In areas close to the coast, almost anything common to southern France, coastal California, South Africa, or most of Italy, will be easy to grow. Plants like Lavender, certain Pinks (Dianthus), Germanders, Sages (both Salvia and Phlomis), Yarrows, Swan River Daisies (Brachyscome), Dusty Miller (Centaurea or Senecio), Snow in Summer (Cerastrium), Perennial Chamomile (Chamaemelum), Feverfew, Bush Morning Glory (Convolvulus cneorum), Perennial Nemesia hybrids, Perennial Twinspur (Dicentra), and scores of others.

Further inland, in the full-up desert, only those perennial flowers with the greatest heat tolerance will live more than one season. The easiest way to select would be to get hold of a copy of the Sunset Western Garden Book at the library, and make a list of the flowers recommended for zone 13--my own climate zone! Most of those will be able to take the 46º C summers likely in the region. Fair warning--some of those plants, though listed as perennials, will act more like cool-season annuals in that climate. Send me a private message and I will send a more well-filtered list. Some won't be available in Manchester, either.

Almost all annuals, including Night-Scented Stock, will grow in both climates. Many of the less heat tolerant, again including Night-Scented Stock, will grow and bloom better in the winter than the summer. I hope all of this helps!

I would check with customs about shipping live plants so it may be worth looking at seeds

Seeds are also likely to be subject to regulation, though most reputable seed companies won't ship disallowed species. If you are bringing your own, you will probably be asked to declare them at customs. I know that Arizona has some pretty ferocious laws about importing seeds or plants. On the other hand, mail order suppliers are usually already prepared to jump through the legal hoops necessary.