Australian and New Zealand Gardening: Convolvulus keeps dying, 1 by Robert_Sc

Robert_Sc wrote:
I have planted several purple-flowered convolvulus on the edge of a rock wall. They seem to do well for a couple of months then they start drying up and then die. I have a drip irrigation that waters them for 1 hr every 2 days - one dripper per plant. We've had very little rain since mid January and temperatures are often in the high 20s. They get direct sun for 4-6h per day. Can anybody tell me what the problem is? Are they being over watered?