Answer: It doesn't sound as though your lilac is getting the care it needs. The first thing you might do is consider moving it. First, find the sunniest spot possible. The soil should be loamy and well drained. Since it's a heavy feeder, fertilize it every other year. Every spring give it some well-rotted compost and dig it in well being careful not to injure the roots. They will enjoy a mulch of hay leaves, wood ashes or pine needles whenever you can give it to them.
When planting, place it in a hole wide enough to take the root without cramping. Fill the hole with a mix of topsoil and compost. Some bonemeal (a cup or so) will go a long way toward giving it a good start. Water it generously each week. By next spring it should perk up and really grow for you.
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