Whaaaaat? Why are lilacs blooming in October? Have you noticed lilacs blooming again this fall? In August, my sainted husband and I noticed a hedge of them blooming like crazy along Old Bluff Road on the way to Sauk City. The shrubs had barely any leaves thanks to a blight this year, but they were showing off their second set of blossoms. In October, our neighbor’s lilacs started blooming.
Horticulturists have a word for this: remontance. It means reblooming. Remontant plants are the goal of many plant breeders … ’cuz who wouldn’t buy a new plant that reblooms. Daylilies and hydrangeas are two plants where lots of hybridization is being done to create rebloomers. There are also reblooming lilacs on the market. The lilacs I’ve noticed flowering lately, however, definitely predate these new cultivars.
Some plants naturally routinely push out a second set of blooms, especially if they are cut back after the first flowers wane. Salvias, veronicas, nepeta and some cranesbill geraniums are a few examples.
There’s another group of plants that are occasionally remontant: spring-blooming trees and shrubs. Think magnolias, forsythia, rhododendrons, crabapples and, yes, lilacs. These plants actually create the buds for the next year’s flowers shortly after blooming. On occasion, a very vigorous growing season or a significant stress triggers the plants to bloom again in the same year. It’s as if they throw caution to the wind and declare, “Why wait?”
So, that’s the scientific explanation for why some lilacs are reblooming this fall. I have an iris that’s also blooming like mad right now. I prefer to think it is doing so for other reasons.
This white-blooming iris was forced upon me by my mother several years ago. I resisted her efforts to give me this plant for years because iris aren’t really a favorite of mine. My mother, however, rarely took “no” for an answer. In March 2019, she died at 94. A few months later when that iris bloomed, I conceded Mom was right. I was glad to have that piece of her in my garden.
In August, I was diagnosed with breast cancer. A few days later, I noticed Mom’s iris was blooming for the second time this year. It bloomed through my two surgeries in September. As I await the start of radiation in late October, that iris is still blooming. It’s Mom’s way of saying, “I know what you’re going through. I’m going through it with you.”
Recently, I discovered that there are, in fact, some rare and expensive iris hybrids that rebloom in fall. Maybe Mom gave me one of those. But I prefer my version: that she found a way to let me know she is with me still. That fits with our shared experience of the garden as a place of wonder and mystery … and blitz.
Patrice Peltier lives in Spring Green and writes regularly for Wisconsin Gardening, Chicagoland Gardening and The Landscape Contractor magazines.