A flowering quince (Chaenomeles species).

It's Japanese Flowering Quince(Chaenomeles speciosa). The most common red cultivar is 'Texas Scarlet', but I can't say that's the cultivar you have or not. I've seen many unnamed ones with similar flowers. They are quite adaptable to different soil types, seem to be relatively drought tolerant. The only thing mine demmand is full sun for flowering. Yours looks like it's doing fine.

Thank you both! I thought that was what it was, but I had no reason for thinking so--that is, no one told me, and I had no familiarity with "quince." The only thing I can figure is, I'm absorbing knowledge at the garden center without realizing it. :)

Flowering quince, anyway, 'Japanese' I would expect to be used for Chaenomeles japonica. This is a short-growing one, often seen in shades of orange. Taller ones, like your example are often hybrids (such as C. x speciosa but not limited to that cross).

Thanks--it is definitely tall, about 7 feet!

I take it back. In Britain Chaenomeles speciosa (it's not a hybrid) is "the well-known, early-flowering japonica, a much-branched, spreading shrub of medium size. Seedling-raised plants bear flowers of mixed colours, but predominantly red." - THE HILLIER MANUAL OF TREES & SHRUBS

Hybrids cultivated include C. x californica and C. x superba.

I think I'll try to pick up that manual! Thanks.

Oddly enough I was given one of these plants just yesterday, and I can quite safely say [judging by your excellent pic] that you have a beautiful Chaenomeles Speciosa 'Rubra'.

Lucky you....Nigel