Lilac season came and went this spring, for many with no blooms.
Many reasons can be the cause of lilacs not blooming. But the Spring of 2017 is different…
Lilacs are known for their durability, their profuse blooming in spite of weather conditions. After all, this is Missouri, and anything can happen. Yet, lilacs usually thrive. So, this phenomenon caused me to wonder…
After talking with Dr Trinklein at University of Missouri, it appears the sudden hard freeze on March 15 froze the tender buds that had emerged prematurely because of the unseasonably warm weather in January and February.
Interestingly, on many older shrubs, there is very little evidence of even the damaged flowers. That means not many flowers were formed to begin with. So, what caused the low bud set?
The 4 main reasons why a lilac (or any other spring-flowering shrub) may not bloom:
1) Lack of sunlight. Though a lilac shrub may have been planted in sunshine, trees can encroach through the years. Lilacs need to have over 6 hours of sunlight each day.
2) Lack of nutrition. As a shrub grows older, we forget that plants still need food. We recommend Fertilome Premium Bedding Plant Food or any other fertilizer high in phosphorus. Apply right now.
3) Pruning at wrong time of year. Flower buds start to develop about mid-August. Pruning anytime from August until when the shrubs bloom in April will remove these potential flowers. Pruning should be done in late spring, right after flowering.
4) Drought. If moisture is lacking during the flower bud setting time, the quality and quantity can be compromised. Though we were not especially dry early last fall, it still could be a cause for the lack of flower buds.