A couple of my A.andreanum hybrids have developped a really curious problem. Every once in a while, the spathe grows on a tall stalk as it would normally but the spadix remains at the crown. What makes it even more weird is that the spathe grows really big as if it cant make up its mind whether to be a leaf or a 'flower'. The normal spathes on this plant are a bright red but these distorted spathes are green shading to red near the stalk.

Can someone tell me whats going on? I'm not new to growing anthuriums but this has really thrown me. The plants are very healthy otherwise. I could make allowances if this happened every time the plant bloomed but its quite erratic... maybe once in 3-4 blooms.

I grow all my anthuriums outdoors in humid, tropical conditions so I doubt whether this problem is a reaction to climatic preferences.

Any ideas anyone?