hibiscus syriacus

The very common (and weedy in places) rose of Sharon (H. syriacus) as said above.

Vini, not all Hibiscus syriacus are as "weedy" as the lovely sterile varieties. The pictured shrub may not produce seeds.

I'm guessing it was planted so near the house to protect it from the colder Michigan temps. It can be transplanted to another location and it doesn't need that trellis for support. Check out the helpful information at the link below.

Here is a link that might be useful: Rose of Sharon