Geography

• The subtropical USDA hardiness zone 10 exists in few places in the continental United States. It exists in a narrow coastal band from central California to San Diego, the southernmost tip of Florida and near the lower Colorado River basin in southeastern California and Arizona.
  
  

Types

• A great diversity of passionflowers grow naturally in South America and thus translate well into USDA hardiness zone 10 where winter frosts don't occur. Seven species worth growing here include Passiflora coccinea, P. edulis, P. foetida, P. phoenicea, P. quadrangularis, P. vitifolia and P. xiikzodz.
  
  

Growing Considerations

• A light frost may kill back the plants to the ground, but they re-sprout. For best growth, plant passionflowers in a sunny location in a moist, well-drained soil that's rich in organic matter. Sand or loam soil is best for these subtropical species.