I've never had any issues with it, and Lilac is used in soaps, for traditional intruments and tablewares, and is even candied and used in tea and some country wines in the Balkans where it is native. I burned a whole 10' bush that had become diseased this past winter.
Lilac that is trimmed at the wrong time will not flower. Prune after flowering, do not prune in spring.
There are a few kinds of bushes that grow tall and quick. Some of the bushes that do this are burning bushes, azaleas and jasmine bushes.
nitrogen
Lilacs blooms are not toxic at all. Neither humans or animals would get sick if they ate purple lilac blooms.
Lilacs smell like a sweet rose and a hint of vanilla. It's a light but a thick scent. Unlike lilac a rose has a more light and thin scent while the lilac has a heavy vanilla-y scent. I prefer the lilac more though! :)
Lilac bushes are not listed on the Cornell University's list of poisonous plants. The University of Arkansas information booklet on poisonous plants has listed Lilac as nonpoisonous with edible flowers (can be used for food). CAUTION: Now don't get lilac bushes confused with the Persian Lilac (aka Chinaberry Tree) which is NOT related to true lilacs at all. The ASPCA Animal Poison Control Center list the Persian Lilac tree as poisonous to dogs and horses.
Leafminers
Yes they do, in the winter.
Are lilac bushes acid loving plants OR DO THEY NEED ALKALINE FERTILIZER
Lilac bushes have been around for a long time. It was growing in southeastern Europe before Christ's time.
it is an idiom
lilac
I just read on Fox Hills Lilac Farm's website that the best time is between April and Oct. They stated that 75% are done in the fall.
Lilac bushes can be pruned in the late winter if the bush is overgrown. However, lilacs should be lightly pruned in early spring after they have finished blooming.
Not to my knowledge
lilac bushes "hibernate" during cold weather like frost and snow like many other plants.
See: http://www.gardenaction.co.uk/plantfinder/lilac-syringa_2.asp April: Feed your Lilac Tree. Scatter a couple of handfuls of bonemeal around (but not touching) the base of the plant and cover with a mulch of well-rotted compost.