Sorry, Ibraham, not quite sure what you mean by "the leaves are tender", except to say that, generally, the new leaves on most plants are a different colour initially, and may darken or lighten, depending on the variety, to match the rest of the bush.

The new leaves are frequently lighter green, softer, and more brittle than mature leaves. They also tend to be more frost tender, if that is the problem. Tenderness to sun is less of a problem in the youngest leaves, since they can adapt to higher light and ultraviolet levels more quickly than mature or "teenaged" leaves. If the new leaves are growing larger and thinner-textured than the older leaves, that may mean that the plant has been moved into too dark an area, and is trying to adapt to the lower light levels.

Hope this helps!

Bamboo, Tugbrethil.. thanks for replying.

The color for new leaves are lighter green. The tag on same plants are Hibiscus rosa-sinensis and each plant have same dark green leaves but one has a thinner leaves. The other ones leaves are thick. They are the same shape, the same size.

I asked the people in garden center and they say it's the same type (Hibiscus rosa-sinensis). I looked online for pictures and it's true both plants are under Hibiscus rosa-sinensis. The only issue im concerned about is that the Hibiscus rosa-sinensis adapts well to the hot/humid summers here in Qatar (the one with thicker leaves). The one with thinner leaves I'm not sure. My neighbor gardner said that the leaves thickens with time & sun exposure!

Well.. I'll have to wait and see the results :-)

Ibrahim, modern Hibiscus rosa-sinensis are complex hybrids of several different species, so different cultivars often have very different leaf shapes and textures. Weirdly, here in the Arizona desert, most of the cultivars that take hot sun the best have thinner leaves. Go figure!