Black eyed susan vine or Thunbergia elata is one of the easiest of summer flowering annual vines to grow. It is ideally suited for hanging basket growth and if fed and watered properly will quickly fill a 12-inch basket with its arrow-shaped leaves and small orange toned blooms (with black eyes). This plant thrives in lots of light but nothing fully hot and direct. The excessive watering created in full hot spots can often lead to root rot in the container. I always did well growing them in a dappled shade container. Full shade will reduce their blooms considerably. The plant appreciates dampish soil but not water-logged so the best thing to do is water thoroughly and then let the soil drain �?if you can touch the soil and your finger is damp, do not water. If on the other hand, you touch the soil and your finger comes away dry, then flood the plant immediately.
Feed at least weekly to keep blooms coming. Use a balanced fertilizer at recommended strengths.
This plant will wilt in extreme heat but it will come back if moved to a slightly less sunny area. If the plant is wilting all over and does not come back, it is quite likely you’ve been overwatering and the roots are dead. Or, underwatered and it has died from neglect.
Black eyed susan vine seed germinates readily when the soil temperature is kept at 72F. It does not appreciate transplanting and does best when sown (one-quarter inch deep) where it is to grow and bloom. If you transplant, do not mess about with the roots but try to keep them from being disturbed in the transplant process.
A new species T grandiflora is coming onto the market. This thicker leaf and larger flowered species is propagated from seed and will be available at better garden shops.