They aren't tropical, he is growing Hibiscus moschuetos.

Right, they are not Hibiscus rosa-sinensis which is the tropical one.

There are several hardy Hibiscus. Yes, you can grow them too.

They're not hard to grow and you can find them at a good large nursery with the perennials, not the tropicals. They can be very late to emerge in spring, so be patient - you may not see stems emerge until early June. Unfortunately, mine seem to be Japanese beetle magnets, and they bloom right when the beetles are here.

I used to grow them in zone 5 and I loved them.

If you can't find them at the nurseries, Parks Seed used to sell the seeds. The ones I grew were called 'Southern Belle" and they were easy to start. The seeds would have to be for next year, though. Happy Hunting.

Perhaps you could ask her for some seeds or cuttings from her plants. If they are already acclimatized for your neighborhood then it should work great. Maybe you'd have something in your garden to share with her in exchange for the seeds/cuttings. We are always swapping plants and seeds in our neighborhood. It works really well since if someone's DH gets too happy with the mower then there will be a replacement for the mowed over plant in someone else's yard who doesn't have such a happy mower in their family.

They are very easy to grow from seed - I got some seeds on ebay. You might be able to start now and plant them out in the fall if you hurry, but spring planting would be better.

You don't need to worry about them being acclimated to your area - zone 7 is plenty warm for them.

Hi!!

There is a possibility that the large hibiscus flowers you saw were the Moy Grande hibiscus which is is a cross between hibiscus mosheutos and hibiscus grandiflorus. They say it's the largest hardy hibiscus flower. Look it up on the internet to buy it.