Late Blooming Wildflowers After Leaf Fall

Observation by Mylanda Forbis

In early October, most of the deciduous trees in my area have already dropped their leaves. The ground under the birch and aspen is covered in yellow/brown leaves, and the branches are nearly bare. What stood out to me is that at the same time, the wildflowers in my yard are still blooming strongly. The fireweed is long gone, but several plants are showing fresh blossoms as if it were midsummer.

This feels unusual compared to past years. Normally by this point, after leaf fall, I would expect flowers to be completely done for the season. Instead, I’m seeing color contrast: bright petals standing out against bare trees and leaf litter.

Possible contributing factors / remarks: - Warmer/rainier than average early fall temperatures may have extended the flowering season. - Lack of early frost could be preventing the usual die-back of blossoms. - Weather conditions this year (rainy September, sunny late days) might explain the overlap between leaf drop and late flowering. - This could also be an example of how plants respond differently to climate shifts: trees may cut off daylight changes, while flowers may be more temperature sensitive.

Questions / hypotheses I’d like to explore: 1. Are other people in the Mat-Su Valley seeing the same late-blooming wildflowers? 2. Is this a pattern tied to warming trends, or just a one-time odd season? 3. Could late blooming affect pollinators or seed production this year?

LEO Says

Thank you for sharing your interesting observations of different trees and plants in the Mat-Su area. We forwarded your observation to Kendra in the Chickaloon area, and she added a few of her own notes from this fall to the discussion. Your remarks about potential contributing factors align well with what other observers and several media articles have noted over the past few years. There are numerous observations and articles from across Alaska that reference “Late Bloomers” in their titles or text. Your contribution will add valuable depth to this ongoing conversation in the LEO Network.

At least some of these are cultivated flowers as opposed to wild flowers. Calendula (the yellow flower) is known for being extremely cold-hardy and will often bloom continuously until the first heavy frost. Marigolds (the red flower) are annuals that are very popular for their long blooming period, often lasting from early summer right until the first hard frost. These are some of the the very few ornamental flowers that can be found thriving in a protected spot in a northern climate like Alaska in October.

Consult by Kendra Zamzow

It was a nice long fall with leaves on the trees longer than usual but this is due to the lack of wind. Yes, it does seem like it has been much warmer than usual, and we are getting rain where in the past we might be getting snow by now. Just a few degrees warmer makes that difference this type of year. Caveat – I have only lived in this area since 2009 so I don’t have a long history of weather patterns here. I am seeing the occasional mosquito still, but I haven’t seen any other pollinators at my place. That doesn’t mean they aren’t here, just that I’m not seeing them.