Why lilacs wont bloom

Insufficient amount of sunlight. Lilac bushes prefer full sun. Without enough sunlight, the plant will not bloom. Transplant shock. If you transplanted your Lilac bush since the last blooming period, they sometimes will miss a year. They need time to recover. Dry summer weather can keep buds from properly forming on the bush. If you are experiencing a summer drought, water the bush deeply once a week. Extremely warm winters. Cold winter weather helps to promote blooms.

Lilacs planted in partial shade will not bloom well. Good care during the first two or three years is also important. Apply a 2- to 3-inch layer of mulch around each shrub to conserve soil moisture and control weeds.

Water lilacs on a regular basis during dry weather. Also, protect lilacs from browsing rabbits by placing wire fencing around the shrubs in fall. While good cultural practices will aid plant growth, some practices may actually inhibit flowering. It is generally not necessary to fertilize lilacs. A pH imbalance or too much or too little of certain chemicals. You might want to have your soil tested. Sometimes, people use high nitrogen fertilizers, especially for their lawns, which will help produce green leaves, while hindering blooming.

Too shady a site. Without enough sunlight, the plant often will not bloom. Lilac bushes prefer full sun. Transplant shock.

You may just have to give your lilacs another year to get over this. Sometimes a late freeze can knock the flowers or the start of the flowers right off the bush.