United Kingdom 
We just planted laurels and mixed with horsemanure but now leaves are turning yellow and they look poorly. Do I need to water them a lot? What could be the reason?
26 May, 2011
Answers
New plants should always be kept well-watered until established, so if they haven't been watered much and they are also wilting, this may be the reason for the yellowing.
Fresh manure can 'burn' the roots of a plant - it should have been matured for at least 6 months, and preferably 1-2 years. A third possible reason is a deficit of nutrients such as nitrogen - manure does contain nutrients, but only a small amount. Try watering with a balanced liquid feed and apply a top dressing of a slow-release fertiliser.
26 May, 2011
Was the manure well-rotted? If it was too fresh, it may well have 'burnt' the roots.
If your weather has been as dry as ours, they might also need watering more than you have done.
26 May, 2011