Shawn wrote > ...None of the former Wilcoxias tolerate the summer heat of Yuma, > even when completely shaded. The native Peniocereus greggii hangs > around and grows, but is finicky here. The Mexican species don't > like the extreme heat, either. This really surprises me. You aren't that much warmer than I am, and they grow here vigorously. Are you sure you're watering them enough? They are not low-water plants here. Leo Martin Zone 9? Phoenix Arizona USA