Hi. I have inherited a garden, and a plant that I believe is periwinkle (vinca?) or possibly morning glory is well encroached on everything in the garden -- mostly rhododendrons and azaleas. The tiny vines entwine themselves around all the plants. And the larger stems seem to be rooted at both ends! I am a new gardener, and I am concerned because the rhodo leaves are turning yellow. Interestingly enough they also have buds. I think they are confused. I am doing my best to get rid of the encroacher (any advice appreciated) but am at a loss as to how to further lep the rhodos and azaleas. Can anyone help? Rose Anne
Iron leaches from the soils during our heavy winter rains and that tends to increase the soil pH. Rhodo sp. need acidic soil to do well. Without a test, I cannot be positive that is the problem for you but many gardeners solve the problem of yellow leaves on rhodos by adding sulphur to the soil at the drip line of the rhodo. As iron leaches, using iron sulphate gives a double whammy for the rhodos. Don't ever put lime around the rhodos when you are liming your grass and flower beds. Try to get a box of iron sulphate (but moss killer products will work as well choosing the one with the highest percentage of iron sulphate) Being in Victoria, your rhodos will likely keep growing much of the winter so feeding with rhodo food is a good idea as well. The vines are not vinca as they are not climbers. A very common problem is Bindweed that has a white flower and is sometimes calle a 'morning glory' . Bindweed has quite extensive roots, long dormancy and is hard to clean up by weeding. It is tricky to control. This URL has excellent recommendations. http://www.omafra.gov.on.ca/english/crops/facts/01-007.htm