By Enjoy
Australia 
Hi! If anyone can shed some light on this problem it would be greatly appreciated. My agapanthus plants are stunted and their leaves deformed. It started with one plant and has since moved onto the next four. The plants have been in the garden bed for over two years and up until now have been very healthy.
25 Jul, 2015
Answers
There is a virus, cant remember the name , that causes this problem. I don't think there is a cure. but a photo would help identify the problem.
25 Jul, 2015
A photo would be helpful. However, this suspiciously sounds like soil compaction. At a certain depth, your soil could be compacted like concrete. This would certainly cause stunted growth.
25 Jul, 2015
Tomato Spotted Wilt Virus was been found in Agapanthus plants in Hobart in 2000 - but you should be seeing some concentric yellow rings here and there, as well as distorted foliage, lack of flowering and stunted growth. Link below to see if yours fit the picture - if they do, you'll have to get rid of the plants, no treatment for viral infection.
http://www.apsnet.org/publications/plantdisease/2000/April/Pages/84_4_491.2.aspx
25 Jul, 2015
Hi Enjoy and welcome to GoY. A photo of the affected plants would be very helpful, just add to your question.
25 Jul, 2015